Dark Chocolate Eclairs Bakealong: Challenge #7


If February means Valentine’s Day, and Valentine’s Day means chocolate… does February mean 28 days of chocolate? Logicians might beg to differ, but we say yes. Thus you have plenty of time to join our Dark Chocolate Eclairs Bakealong challenge, a heartfelt tribute to the pleasures of deep-dark chocolate.

Take the Dark Chocolate Eclairs #bakealong challenge, just in time for Valentine's Day. Click To Tweet

Now, you might think éclairs are way beyond your experience level but trust me — they’re not. If you can stir together flour, melted butter, and water, you’ve got the savvy for your shells. If you can simmer milk and cocoa in a saucepan, then mix it with egg yolks, sugar, and cornstarch (plus chocolate and butter), you’ve nailed the filling. And the glaze on top? Just two simple ingredients.

Our February Dark Chocolate Eclairs Bakealong challenge isn’t quick; but its multiple steps can be spaced out to fit your schedule. And the result?

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Deep-dark deliciousness!

Follow along with me as I show you how to make these éclairs — and share some tips I discovered in the process.

First, preheat the oven to 425°F. Lightly grease (or line with parchment) two baking sheets.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Make the pastry

Combine the following in a saucepan:

1 cup water
8 tablespoons (1/2 cup) unsalted butter
3/8 teaspoon salt

Heat until the butter has melted, and bring to a rolling boil.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Add 1 1/4 cups (5 1/4 ounces) King Arthur Unbleached All-Purpose Flour all at once, stirring vigorously. Return the pan to the burner and cook over medium heat, stirring all the while, until the mixture smooths out and follows the spoon around the pan. This should take far less than a minute; a few good strokes is really all you’ll need.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Remove the pan from the heat, and let the mixture cool for 5 to 10 minutes. It’ll still feel hot, but you should be able to hold a finger in it for a few seconds. If you have a digital thermometer, the temperature should be below 125°F.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Transfer the mixture to a mixer, and beat in 4 large eggs one at a time; it’ll look curdled at first, but when you add the last egg it should become smooth. Beat for at least 2 minutes after adding the last egg.

If you have a pastry bag, scoop the batter into the bag, and add a 3/4″ plain tip.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

If you don’t have a pastry bag, do what I did: take a plastic bag, stuff it in a tall glass, and scoop the batter into the bag. Push the batter to the bottom of the bag, and cut off one of the two corners, making a hole about 3/4″ in diameter.

Tip: Use a plain, inexpensive plastic bag, not one with gusseted corners that open outward. Cutting the corner off a gusseted bag leaves two holes, not one — as I discovered in my first DIY pastry bag attempt!

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Shape the éclair shells

Pipe the batter onto the pan in 5″ logs about 3/4″ in diameter.

If you don’t have a pastry bag and choose not to DIY with a plastic bag, you can shape the shells using a spoon and your wet fingers; but it can be a sticky undertaking. I highly recommend piping with a bag.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Make sure to squeeze as much of the sticky batter out of the bag as possible; a bowl scraper works well here. You should be able to make about 20 éclair shells out of the recipe.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Bake the shells

Bake the shells for 15 minutes, then reduce the oven temperature to 350°F and bake for an additional 25 minutes, until they’re a medium golden brown.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Remove the shells from the oven. Make a small slit in the top (or on the side) of each, and return them to the oven to bake for 5 more minutes, to allow any steam to escape.

Let the shells rest until they’re cool enough to handle. If you plan on filling and finishing them right away, split each in half to make top and bottom pieces.

Tip: If you’re time-challenged, set the shells aside, without splitting, for up to a couple of days before filling. Don’t wrap them tightly in plastic, but rather loosely in a partially open plastic bag, or covered with a large cake cover.

Make the dark chocolate filling

Gather these ingredients:

1/2 cup sugar
5 tablespoons cornstarch
4 large egg yolks
2 cups whole milk
1/2 cup King Arthur Triple Cocoa Blend, or Dutch-process cocoa
1/3 cup chopped unsweetened baking chocolate (2 ounces)
1 tablespoon unsalted butter

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Tip: Store-bought unsweetened baking chocolate used to come in 1-ounce squares; now it comes in 1/4-ounce rectangles. Don’t be fooled into thinking each of these rectangles is the equivalent of the 1-ounce squares of old! (Luckily, they’re clearly marked.)

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Combine the sugar and cornstarch in a mixing bowl.

Whisk in the yolks; the mixture will look like scrambled eggs.

Bring the milk and cocoa just to a simmer in a saucepan set over medium heat.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Pour about a quarter of the hot milk/chocolate into the yolk mixture, whisking until incorporated.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Return the egg yolk mixture to the saucepan, and put the pan back on the burner over medium heat.

Cook, stirring constantly, until the mixture becomes very thick, and just barely starts to boil. Remove the pan from the heat.

Add the baking chocolate and butter, stirring until melted and smooth.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Transfer the filling to a bowl.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Cover it with plastic wrap, pushing the wrap right down onto the filling; this will prevent it from developing a tough top skin. Cool to room temperature, then refrigerate for at least 2 hours. The filling can chill in the fridge up to several days, so you definitely have flexibility fitting it into your schedule.

Tip: To make classic éclairs stuffed with vanilla filling, use a half recipe of our Pastry Cream, omitting the whipped cream at the end.

Eclairs are best served the same day they’re filled and iced. Let’s assume you’ve reached that day; let’s finish these éclairs.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Make the glaze

Combine 2/3 cup chopped semisweet chocolate (or chocolate chips) and 1 1/2 teaspoons corn syrup in a medium heat-safe bowl.

Heat 1/2 cup heavy cream to simmering, then pour it over the chocolate. Let the mixture sit for about a minute, then stir until you’ve made a smooth glaze. The glaze may be quite thin at the outset, but will thicken as it cools. 

Tip: This amount of glaze is more than enough for the éclairs, if you simply dip their tops. Either drizzle additional glaze over the éclairs, or refrigerate any leftover glaze and pour it over ice cream.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Assemble the éclairs

At last! We’re ready to put all the pieces of this project together.

If you hadn’t already split the shells into top and bottom pieces, do so now.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Fill the shells

Pipe or spoon the filling into the pastries. You’ll use just over 1 ounce (30g) filling for each of the 20 éclairs.

See how soft my filling looks? Operator error. I inadvertently cooked the filling over high heat, and it became lumpy; then I had to put it into the blender to smooth out the lumps, and it “broke” — the cornstarch lost its oomph. Ah well, life is full of very minor tragedies… and the éclairs still tasted just fine.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Glaze the tops

You can set the éclair tops over the filled bottoms and drizzle the glaze on top. But for even application, I prefer to dip the tops right into the glaze, then carefully set them atop the bottoms.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Oh yeah.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

Make gluten-free éclairs — or fill with vanilla cream

I tried a batch of éclairs using our newest gluten-free flour, Measure for Measure, and was totally impressed. The gluten-free shells are every bit as crisp and high-rising as the original version.

For those looking for a more traditional éclair, I also filled this batch with vanilla pastry cream. A half batch of our Pastry Cream recipe (sans the whipped cream added at the end) will yield enough to fill the éclairs, though not quite as fully as the chocolate filling does.

For ease of preparation, you can also substitute your favorite vanilla pudding mix prepared with cream instead of milk, and spiked with a teaspoon of vanilla extract.

Dark Chocolate Eclairs Bakealong via @kingarthurflour

A final touch

Our food photographer loves beautifying recipes — and you can see what a great job she does. Piping the filling with a star tip adds an elegant look, while a sprinkle of diced shelled pistachios adds color, flavor, and crunch to these pastries.

Are you ready to take our February Dark Chocolate Eclairs Bakealong challenge? Let us know how it goes in comments, below.

Interested in more? See our complete collection of Bakealong recipes.

PJ Hamel

PJ Hamel grew up in New England, graduated from Brown University, and was a Maine journalist before joining King Arthur Flour in 1990. PJ bakes and writes from her home on Cape Cod, where she enjoys beach-walking, her husband, two dogs, and really good food!


  1. Kristen B.

    How does pate au choux behave at altitude? My daugher’s in the high desert in AZ and wondered how to modify…

    1. Susan Reid

      Hi, Kristen. Since water boils at a lower temperature at altitude, it’s probable that the pastry shell won’t rise as much as it does at lower elevations. Most of the structure in the pastry is from the eggs, not the flour, so I think it’s worth a try. If I were doing these at my brother’s house in CO (8100 ft) I would increase the oven temperature by 25°F to help everything happen quicker. Susan

  2. tmana

    I grew up using the puff pastry recipe in the Antoinette Pope School of Cooking cookbook, using their pastry cream recipe for the filling. I’ve had pastry bags and tips since I bought them in college.
    If you have, or can find, a “Bismarck” (filling) tip (#230 or #231) you won’t have to split open my puff pastries (or jelly donuts) to fill them. (Unless you’re able to pipe your filling with a star tip, split-open filled pastries tend to look home-made.)

    That said, I find I usually need to double my pastry cream recipe to have enough to fill my puff pastries…

    1. Susan Reid

      Completely agree, Bismarck tips are perfect for this task, and the end result is a lot less messy to eat! Susan

  3. Margaret R. Urrutia

    A friend send me, this and i love it! Idont like to be to sweet! And you have alternative, to does dont like to much, sugar. You have a great, bloq! The Lord bless, you! And keep the good work! I sing up! And very happy, to recieve, your e-mail!

  4. laurabun

    Technically everything came together as it should. The chocolate filling can stand was delicious and can stand alone as a pudding. But the flavor of the pastry was very lacking and only got worse in the ensuing days. Since it was just my husband and myself, most of these were tossed, which is really a shame considering the cost and time of production.

    1. The Baker's Hotline

      Hi Laura, we’re sorry to hear the shell of the eclairs weren’t as tasty as the cream itself. Choux pastry is known for being more of a bit player than the star of the show–think of it as the vehicle for the pastry cream, if you wish. It sounds like next time you might just want to cut right to your favorite part and whip up a batch of chocolate pastry cream. It makes an elegant dessert when portioned into individual ramekins and topped with fresh berries. There’s nothing wrong with that! Kye@KAF

    1. The Baker's Hotline

      We haven’t tried that substitute, Kalena, but it may help to know that you can simply leave the corn syrup out of the glaze if you prefer. It helps to make for a smoother, shinier glaze, but it’s not strictly necessary. Mollie@KAF

  5. Patsy

    I made these. I had a hard time getting the proper size for the pastry even though I cut a 3/4 inch opening in the pastry bag. I guess 3/4 inch diameter was not what the recipe meant. they came out rather hard. the inside tasted like chocolate pudding, according to one of our guests. I’m not a big chocolate fan and was sorry I’d not made any of the vanilla filling for these. Husband liked them a lot. I’d call it okay, but likely not make the recipe again. too much work and not all that great.

    1. PJ Hamel, post author

      Patsy, sorry these weren’t up to your expectations. Piping them 3/4″ does make them smaller than the typical bakery éclair, it’s true. I prefer them with vanilla pastry cream filling myself, but thankfully there are those who love them with chocolate all the way through — like your husband. 🙂 PJH

  6. Jane P Borden

    Hi, I just can’t make eclairs. I have tried this recipe and others and they always come out kind of flat. The inside is kind of hallow but they never puff up. What am I doing wrong?

    1. The Baker's Hotline

      It can be so frustrating when that happens, can’t it, Jane? We’ve certainly experienced this kind of disappointment ourselves. If your shells aren’t puffing well, it could be that your choux may have been too thin (from not cooking the flour mixture long enough and/or overbeating) or that you’re piping your shells wide and flat rather than narrow and tall. It could also be that the oven temp is simply a bit too low. It’s important for the oven to be hot enough to create steam to leaven the pastry. If we can help troubleshoot any further, please feel free to give our Baker’s Hotline a call at 855-371-BAKE. Mollie@KAF

  7. carol

    Is it possible to make the batter and only bake half at a time. My oven does best when I only bake on one rake at a time. I tried using 2 racks this morning and the top of the shells came out great but the bottoms were not flat which made slicing them evenly kind of a problem. I was able to salvage enough for the 10 I actually needed so not a major disaster and I’m excited to finish putting them together with the vanilla pastry cream which came out awesome. Now I’ll have some extra cream to eat the reject shells with.

    1. The Baker's Hotline

      Sometimes the leftover rejects are just the perfect treat for the baker, Carol! It could work to allow one tray of eclairs to rest in the fridge while the other bakes or to simply cut the recipe in half and only make one tray. If you found that the bottom of your shells were almost concave, this could also be the result of not slitting the shells and returning them to the oven to finish baking quickly enough. Without the slit/vent, the steam trapped inside can distort the shape, something we have definitely learned the hard way ourselves. Hope this helps! Mollie@KAF

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