90grams(Scant ½ cup / 3 ½ ounces) granulated sugar,plus more for dusting ramekins
300grams(10 ½ ounces) good quality bittersweet chocolate,chopped
3large egg yolks
300milliliters(1 ¼ cups) milk
15grams(1 ½ tablespoons / ½ ounce) potato starch or cornstarch
Confectioners’ (icing) sugar,if desired
Set the oven rack in the lower third of the oven and preheat the oven to 450°F (230°C). Brush soft butter on the bottom and sides of 6 (8 ounce/1 cup) ramekins and dust the insides with about 1 teaspoon each of sugar, rotating to ensure the entire interior is evenly coated, and knocking out any excess.
Add the egg whites to the bowl of an electric mixer fitted with the whisk attachment and beat for about 3 to 4 minutes on medium speed (#6 on a Kitchenaid mixer) until frothy but not stiff. Next, add the sugar and continue beating for about 5 to 6 minutes on medium speed, until you achieve glossy stiff peaks.
Add chopped chocolate to a double boiler or a metal bowl set over a pot of simmering water. Make sure the bowl does not touch the simmering water below. Heat until the chocolate in the bowl melts, stirring occasionally, and then turn off the heat but leave the bowl over the water to keep it hot/melted.
Meanwhile, place the egg yolks in a large mixing bowl and set it beside the stove. Whisk together the milk and potato starch (or cornstarch) in a small saucepan. Heat over medium heat and bring to a bubble, whisking continuously until thickened, about 10 minutes from start to finish. Slowly whisk the hot milk mixture into the egg yolks about a tablespoon at a time to ensure you don't cook the eggs. Whisk until smooth.
Remove the bowl of melted chocolate from the heat. Incorporate a dollop of the whipped egg whites into the milk mixture. Then fold a dollop of whipped whites into the melted chocolate. Combine the 2 mixtures until smooth, and then carefully fold in the remaining egg whites until no streaks or lumps remain. Use a flexible rubber spatula to do so, as this will help you reach the bottom of the bowl and combine everything well.
Spoon the soufflé batter into each prepared ramekin. Use a straight edge (like an offset spatula, back of a butter knife, or bench scraper) to level off the top of each (wipe off any drips of batter with a damp paper towel). Next, run your finger around the inside edge of each ramekin to create a lip. It will slightly separate the batter from the edge of the ramekin, and will help it rise even and tall. The lip will not be very visually obvious but it will still serve its purpose. If you have enough extra batter, you could make an additional soufflé or discard it.
Arrange the filled ramekins on a rimmed baking sheet, place in the oven and immediately lower the temperature to 400°F (200°C). Bake for about 15 minutes or until puffed up about 1-to-1 ½ inches from the top of the ramekins. Once they are done they shouldn't really wobble if you give the pan a slight shake. Do not open the oven door until you're ready to check if the soufflés are done, as this could cause them to deflate (use your oven light and peek in the oven window instead!).
Dust with confectioners’ sugar if desired and serve immediately.
The ingredients in this recipe are easily divisible by 3, using the metric values in particular. Thus you can conveniently reduce this recipe to make 2 or 4 soufflés if you prefer. Just note that if you reduce the recipe the eggs will require less time to whip, and the milk/starch will take less time to cook, so adjust those times as needed.
At the Ritz Paris they use equal parts Valrhona Manjari chocolate (64% cocoa) and Valrhona Guanaja chocolate (70% cocoa), 150 grams of each. I use a 50/50 combination of 60% and 70% chocolate bars for mine, but you could just stick with one variety of high quality chocolate if you prefer.
Chocolate soufflés are only as good as the chocolate you use, so use good quality baking chocolate such as Valrhona, Scharffen Berger, Ghiradelli, Lindt, Green & Black's, Baker's, or Moser Roth (from Aldi). Do not use chocolate chips as they contain stabilizers and will not yield the best results.
It's easier to separate eggs when they are cold, but easier to whip egg whites when they are at room temperature.
I've tested this recipe with whole milk and also with low-fat milk and honestly it not only works but is delicious in both cases. I would suggest using whichever type you have on hand, but the added fat from whole milk won't hurt.
This recipe is naturally gluten-free as it does not contain any flour!