Creating a Chocolate Mousse Cake with this recipe is simple! Follow these easy steps to achieve a delectable result:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

2. Combine Dry Ingredients: In a bowl, mix together flour, sugar, cocoa powder, baking powder, baking soda, and salt.

3. Add Wet Ingredients: In a separate bowl, whisk together the eggs, milk, vegetable oil, and vanilla extract until well combined.

4. Mix Together: Pour the wet mixture into the dry mixture and stir until smooth. Gradually add the boiling water and mix until well incorporated.

5. Divide and Bake: Divide the batter evenly between the two prepared cake pans. Bake in the preheated oven for 25-30 minutes or until a toothpick inserted in the center comes out clean.

6. Cool the Cakes: Once baked, remove from the oven and allow to cool in the pans for 10 minutes. Then, turn them out onto wire racks to cool completely.

7. Prepare the Mousse: In a microwave-safe bowl, melt the chocolate chips and butter together. Stir until smooth and allow to cool slightly.

8. Whip the Cream: In a separate bowl, beat the heavy whipping cream, powdered sugar, and vanilla extract until soft peaks form.

9. Combine Mousse: Gently fold the whipped cream into the chocolate mixture until fully combined. Ensure not to deflate the whipped cream to maintain the airy texture.

10. Assemble the Cake: Once the cakes are completely cool, place one layer on a serving platter. Spread half of the mousse on top. Place the second layer of cake on top and spread the remaining mousse over it.

11. Chill: Refrigerate the assembled cake for at least 2-3 hours, or overnight for optimal firmness.

12. Garnish and Serve: Before serving, garnish with chocolate shavings, berries, or whipped cream if desired.

Each step will guide you in creating a Chocolate Mousse Cake that’s not only delicious but also visually stunning!