Soft Creamy Chocolate Mousse Cake

Ingredients

• 25 g Unsweetened Cocoa Powder (will be mixed with hot water)
• 45 g Hot Water (for dissolving cocoa powder)
• 3 large Eggs (separated; use room‑temperature eggs)
• 1 pinch Fine Sea Salt (for egg whites)
• 285 g Granulated Sugar (divided: 60 g for egg whites, 20 g for yolks, 30 g for yolk‑milk mix, 15 g for whipped cream, 160 g for glaze)
• 50 g Cake Flour (sifted before folding into batter)
• 20 g Vegetable Oil (neutral‑flavored oil)
• 1 sheet Baking Paper (to line the baking pan)
• 70 g Dark Chocolate (70 % cocoa, chopped)
• 100 g Whole Milk (warmed)
• 1 tsp Instant Coffee (adds depth to mousse)
• 6 sheets Gelatin Sheets (1.5 g each; bloom in cold water before use (3 for mousse, 3 for glaze))
• 370 g Heavy Cream (chilled; 250 g for mousse, 120 g for glaze)
• 8 whole Strawberries (for garnish, washed and halved)
• 30 g White Chocolate (melted for drizzling)

Instructions

1. Make Cocoa‑Water Mixture

   Add 45 g hot water to 25 g unsweetened cocoa powder in a small bowl and whisk until smooth.

   Time: PT2M

2. Whisk Egg Whites

   Separate the three eggs. In a clean bowl, whisk the egg whites with a pinch of fine sea salt on medium speed for about 30 seconds until foamy.

   Time: PT2M

3. Add Sugar to Egg Whites

   Add the 60 g granulated sugar in three equal batches, whisking 30 seconds between each addition, until the whites form stiff glossy peaks.

   Time: PT3M

4. Prepare Egg Yolk Mixture

   In another bowl, whisk the 3 egg yolks with 20 g sugar until the sugar is fully dissolved.

   Time: PT1M

5. Combine Cocoa and Yolks

   Stir the cocoa‑water mixture into the yolk mixture until evenly combined.

   Time: PT1M

6. Fold First Half of Egg Whites

   Gently fold in half of the whipped egg whites using a spatula, moving from the bottom of the bowl upward to keep the batter airy.

   Time: PT1M

7. Incorporate Cake Flour

   Sift 50 g cake flour over the batter and fold using the same gentle motion until just combined.

   Time: PT2M

8. Fold Remaining Egg Whites

   Add the remaining half of the egg whites and fold until the batter is uniform.

   Time: PT1M

9. Add Oil and Finish Batter

   Stir in 20 g vegetable oil until just incorporated. The batter should be glossy and smooth.

   Time: PT1M

10. Bake the Sponge

    Pour the batter into a 40 × 25.5 cm pan lined with baking paper, smooth the surface, and bake in a pre‑heated oven at 180 °C for 15‑17 minutes, or until a toothpick comes out clean.

    Time: PT15M

    Temperature: 180°C

11. Cool the Sponge

    Remove the baking paper, transfer the cake to a wire rack and let it cool completely (about 30 minutes).

    Time: PT30M

12. Prepare Chocolate for Mousse

    Finely chop 70 g dark chocolate and set aside.

    Time: PT1M

13. Make Chocolate‑Milk Base

    Whisk 2 egg yolks with 30 g sugar until pale, then slowly whisk in 100 g warm milk. Place the mixture over low heat, add 1 tsp instant coffee, and heat just until it thickens (do not boil). Remove from heat.

    Time: PT2M

14. Add Gelatin to Base

    Stir in 3 bloomed gelatin sheets (1.5 g each) until fully dissolved.

    Time: PT1M

15. Combine Chocolate and Cream

    Pour the warm chocolate‑milk mixture over the chopped dark chocolate, stirring until smooth. In a separate bowl, whip 250 g heavy cream with 15 g sugar to soft peaks, then gently fold the chocolate mixture into the whipped cream in three batches.

    Time: PT4M

16. Cut the Sponge

    Using a 16 cm square mold, cut the cooled sponge into two equal sheets.

    Time: PT5M

17. Adjust Mousse Consistency

    If the mousse feels too thick, microwave it for 10‑15 seconds, then stir to loosen.

    Time: PT1M

18. Assemble the Cake

    Place one sponge sheet on a serving plate, spread half of the mousse evenly, then place the second sheet on top and spread the remaining mousse. Smooth the top.

    Time: PT5M

19. Chill Assembled Cake

    Refrigerate the assembled cake for at least 4 hours (or overnight) to set the mousse.

    Time: PT4H

20. Prepare Chocolate Glaze

    Sift 70 g cocoa powder into a saucepan, add 120 g hot water and stir until smooth.

    Time: PT2M

21. Add Cream and Sugar to Glaze

    Stir in 1/3 of the warm heavy cream (≈40 g) followed by the remaining cream and 160 g sugar. Bring the mixture to a gentle boil, then remove from heat.

    Time: PT5M

22. Incorporate Gelatin into Glaze

    Add the remaining 3 bloomed gelatin sheets, whisk until fully dissolved and no lumps remain.

    Time: PT1M

23. Cool Glaze to Proper Temperature

    Allow the glaze to cool to 30‑35 °C (warm to the touch) before pouring over the cake.

    Time: PT5M

    Temperature: 30-35°C

24. Glaze the Cake

    Place the chilled cake back on the rack and slowly pour the glaze over the top, allowing it to flow down the sides. Refrigerate for another 1‑2 hours to set.

    Time: PT5M

25. Finish and Serve

    Drizzle melted white chocolate over the set glaze and garnish with fresh strawberries. Slice and serve chilled.

    Time: PT5M

Nutrition Facts

Calories

350

Protein

5 g

Carbohydrates

45 g

Fat

18 g

Fiber

3 g

Ingredient Substitutions

• Instead of Unsweetened Cocoa Powder: Dutch‑processed cocoa powder
• Instead of Eggs: egg replacer (not recommended for mousse)
• Instead of Granulated Sugar: caster sugar
• Instead of Cake Flour: all‑purpose flour (with 2 % extra starch)
• Instead of Vegetable Oil: canola oil, melted butter
• Instead of Baking Paper: silicone baking mat
• Instead of Dark Chocolate: semi‑sweet chocolate
• Instead of Whole Milk: 2 % milk
• Instead of Instant Coffee: espresso powder
• Instead of Gelatin Sheets: powdered gelatin (1 g powder = 1 sheet)
• Instead of Heavy Cream: whipping cream
• Instead of Strawberries: raspberries
• Instead of White Chocolate: cocoa butter glaze

Equipment Needed

• Mixing Bowl
• Hand Whisk
• Fine Mesh Sieve
• Silicone Spatula
• Baking Pan (40 × 25.5 cm)
• Oven
• Saucepan (medium)
• Microwave (optional)
• Square Mold (16 cm)
• Measuring Scale
• Cutting Board
• Chef’s Knife
• Refrigerator

Critical Steps — Do Not Skip

• Folding the egg whites without deflating the batter
• Fully dissolving gelatin sheets in both mousse and glaze
• Cooling the chocolate glaze to 30‑35 °C before pouring
• Chilling the assembled cake for at least 4 hours

Chef Tips from the Video

• Separate eggs while they are cold; then let them come to room temperature for better volume.
• Sift cocoa powder with the hot water to avoid lumps.
• Use a kitchen scale for all measurements – chocolate cakes are sensitive to weight.
• For a shinier glaze, strain it through a fine mesh before cooling.

Troubleshooting

Storage

Refrigerator: Store sealed cake in the refrigerator for up to 4 days.

Freezer: Not recommended; texture of mousse may change.

Room temperature: Can sit at room temperature for up to 2 hours after glazing.

Make-Ahead Tips

• Bake the sponge a day ahead and store it wrapped in plastic.
• Prepare the chocolate mousse up to the folding stage and keep refrigerated; add the final fold just before assembly.
• The glaze can be made 2‑3 hours ahead; keep it warm (around 30 °C) before pouring.

Frequently Asked Questions