This perfect mousse au chocolat recipe (chocolate mousse) from Julia Child is rich, decadent, and airy, with hints of orange, coffee, and a delicate touch of sea salt. If you're looking for a traditional French chocolate mousse, this dessert is for you! Plus, it’s easy to make ahead, scale up or down, and customize.
Some recipes are classics for a reason, and Julia Child's chocolate mousse from Mastering the Art of French Cooking is one of those. I've seen many variations across the internet, some with less sugar, some with rum instead of orange liqueur; the list goes on.
Last week, while in the throes of a chocolate fix, I decided to try the original version—and it did not disappoint. In the span of a week, I made it four times. I loved the slightly stretchy texture, with notes of chocolate and orange. It was somehow decadent and light at the same time.
Recipe Adaptations
I tested several variations of this mousse, and as long as you follow the core techniques, it's pretty forgiving. Just be ready for an arm workout because you will need to do a LOT of whisking!
Here's what I've changed from the original:
- While I love a good chocolate-orange combo (see my chocolate orange yogurt pots de creme), I initially found the liqueur slightly "alcoholic" tasting and instead reduced the amount slightly.
- I prefer instant espresso (aka espresso powder) to brewed coffee in desserts because (1) I love intense coffee flavors and (2) I am too lazy to make a fresh cup. Want a stronger coffee flavor? Use 1 tablespoon instant espresso.
- The amount of sugar and the use of semi-sweet chocolate were too sweet for me, so I reduced the sugar slightly and now recommend bittersweet instead and a generous sprinkling of flaky sea salt.
For more tasty French-inspired recipes, try my french hot chocolate, blueberry clafoutis (another Julia Child favorite) or brioche cinnamon rolls.
Ingredient Notes
- Chocolate: The original recipe calls for semi-sweet chocolate (64%+ cocoa), though I recommend bittersweet (70%+ cocoa) for a better balance of sweetness.
- Do: Whatever you go for, select the best quality chocolate you can find. This dessert is a special treat, so it's worth the splurge. I love Guittard, Valrhona, Callebaut, or your favorite single-origin chocolate bar.
- Don't: Avoid chocolate chips or any sort of product with added ingredients that can prevent the chocolate from melting properly or lead to a poor textural result (i.e. soy lecithin, artificial flavorings, etc.)
- Orange Liqueur: Replace the orange liqueur with 2 tablespoons of orange juice and 1 teaspoon zest. Note that this substitution will cause a slight change in texture, yielding an "airier" version than the original. It's still very delicious, though!
For a full list of ingredients and their quantities, please refer to the recipe card.
A Note on Raw Eggs
For this recipe, which uses raw eggs, choose the freshest, highest-quality eggs from a trusted source, or opt for pasteurized eggs to minimize any risk of contamination while ensuring the mousse's flavor and texture shine.
Note that not all brands of liquid pasteurized egg whites will whip into a meringue, so check the label. In fact, I couldn't find one usable for meringues, so I don't have a recommendation right now, but please drop me a note if you do!
How to Make This Recipe
Step 1 - Heat and cool the yolks: In a heatproof bowl, whisk the egg yolks and sugar together until the color changes from bright yellow (Image 1) to pale yellow (Image 2) and the mixture thickens considerably. It should drip, like a ribbon, then slowly disappear back into a smooth texture (Image 3). Stir in the orange liqueur.
Prepare your double boiler. Place the mixture over a not-quite-simmering pot of water, and continue whisking frequently until the mixture lightens in color and becomes too hot to the touch.
Remove from the heat, and continue stirring in a bath of cold water until the mixture thickens again into that "ribbon-like" texture. Set aside (Image 4).
Step 2 - Melt the chocolate: In a separate bowl, combine the chocolate, espresso, and hot water. Set over the pot of hot water, and whisk until melted (Image 5). Turn the heat off, then whisk in the butter until incorporated (Image 6). Mix the melted chocolate into the egg yolk mixture (Image 7). Set aside.
TIP: If your chocolate starts looking a bit grainy or greasy, it may have seized up. But no worries, this is easy fixable. Just add a teaspoon of cold water at a time until it smooths out again before incorporating into the eggs.
Step 3 - Whip the egg whites: In a stand mixer, or with an electric hand mixer, whip the egg whites with a pinch of salt to soft peaks. Then add the sugar, and continue whipping to stiff peaks (Image 8). Be careful not to over beat!
Step 4 - Add the whites: Gently stir in ¼ of the whites (yes, you can stir) until fully incorporated (Image 9). Then, gently fold in the remaining whites (Image 10) until just a few small streaks remain (here, be careful not to over-stir) (Image 11).
Step 5 - Chill: Transfer the mousse to a large container (or individual ramekins or bowls), wrap with plastic wrap, and chill for at least 4 hours, ideally overnight (Image 12). Serve with a pinch of flaky salt and whipped cream if desired. Enjoy!
Storage: Leftovers can be stored in an airtight container (or tightly wrapped) in the fridge for 2 - 3 days. However, I recommend serving it within 24 hours of preparation for the freshest flavor. You can also store them in the freezer for 2 - 3 weeks. Allow to thaw slightly before serving or enjoy as a creamy, "semi-freddo"-esque treat!
Expert Tips
- For a fun presentation, top mousse with homemade whipped cream and chocolate shavings!
- Know when to whisk vigorously and when to gently fold. The egg yolks need to be whisked very well to create that slightly chewy, stretchy texture. The egg whites, on the other hand, need to be very gently incorporated so that the air bubbles don't deflate. That's what gives it a nice, airy structure.
- Use good quality ingredients. Other than technique, high-quality fresh eggs and good chocolate are the key to a good mousse.
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Happy eating! Love, KarishmaJulia Child's Chocolate Mousse
Ingredients
- 4 large eggs, separated
- 150 grams caster sugar, see notes
- 3 tablespoons orange liqueur, see notes
- 170 grams high-quality bittersweet chocolate, 70% - 74% cocoa | chopped
- 1 ½ teaspoons espresso powder
- 60 ml hot water
- 170 grams unsalted butter, cut into ½-inch cubes and softened to room temperature
- 1 teaspoon Diamond-Crystal Kosher Salt, or ½ teaspoon Morton Kosher Salt or Sea Salt
- 12 grams granulated sugar
- Flaky sea salt, optional, for topping
For the Chantilly cream (optional):
- 238 grams heavy cream
- 1 teaspoon vanilla paste
Instructions
- Set up the double boiler: This recipe requires you to heat multiple ingredients in a double boiler situation, so you'll need two separate medium heatproof bowls that can rest atop a medium saucepot with a couple of inches of simmering water such that the bottom of the bowls do not touch the water. Set your saucepot with water over medium-low heat. Bring to just below a simmer (no more than 190℉/87℃). Separately, fill a large bowl with cold water and set aside.
- Whisk the egg yolks: While the water heats up, vigorously beat 4 large egg yolks and 150 grams caster sugar in a medium bowl until the mixture has thickened significantly and turned pale yellow, about 3 - 4 minutes.Note: If ready, when you lift the whisk, it should flow off in a ribbon that sits on the surface for a few seconds before dissolving back into the bowl. This step is critical to developing a slightly "chewy" mousse texture.
- Heat and cool the yolks: Whisk in 3 tablespoons orange liqueur, then set over the saucepot and continue whisking for 3 - 8 minutes until the mixture is foamy and too hot for your finger to touch, about 178℉/81℃.Turn the heat off (but do not discard the water, you'll need it again), and place the bowl with egg yolks over the bowl of cold water, and continue whisking again until the mixture has fully cooled to room temperature and thickened once again into that ribbony texture. Set aside.
- Melt chocolate: In another medium bowl, add 170 grams high-quality bittersweet chocolate, 1 ½ teaspoons espresso powder, and 60 ml hot water. Bring the saucepot back to a bare simmer, and place the bowl over the pot until the chocolate is fully melted, about 2 - 4 minutes.Remove from the heat, then add 170 grams unsalted butter, whisking until fully incorporated. Mix the melted chocolate into the egg yolks. Note: Did your chocolate "seize" up and turn slightly greasy? No worries, just vigorously whisk in a teaspoon of cold water at a time until it comes back together.
- Beat the egg whites: In a stand mixer (or with an electric hand mixer), beat 4 egg whites and 1 teaspoon Diamond-Crystal Kosher Salt until soft peaks form. Add 12 grams granulated sugar and continue beating until stiff peaks form. Stir in (don't fold) a quarter of the egg whites into the chocolate-egg mixture, then gently fold in the remaining egg whites until just barely incorporate. A few streaks of egg whites should remain so as not to overbeat and deflate the mixture.
- Chill: Transfer the mousse into a large serving bowl, individual ramekins, or glass pudding cups. Cover with plastic wrap, and store in the fridge for at least 4 hours, but ideally overnight.
- Serve: To serve the mousse, top with a bit of Flaky sea salt or the Chantilly cream (optional, recipe below). Enjoy immediately!
For the Chantilly cream (optional):
- Just before serving, make the whipped cream.In a stand mixer (or an electric hand mixer), beat 238 grams heavy cream and 1 teaspoon vanilla paste until stiff peaks form. Top mousse as desired, and enjoy.
Notes
Nutrition
The nutritional information on this website is only an estimate and is provided for convenience and as a courtesy only. The accuracy of the nutritional information for any recipe on this site is not guaranteed.
Karishma
Owner's Rating: One of the most delicious desserts I've eaten in recent months. It is decadent, chocolaty, and the texture is smooth, creamy, and airy.