Chocolate Lemon Custard Cake

How to Make Chocolate Lemon Custard Cake

1. Prep pans and oven

   Heat your oven to 350°F and position a rack in the center.

   Grease two 8-inch round cake pans, then line the bottoms with parchment and lightly flour the sides.

2. Mix dry ingredients

   In a large bowl whisk together the flour, cocoa powder, sugar, baking soda, baking powder, and salt.

3. Combine wet ingredients

   In a separate bowl whisk the eggs, milk, sour cream, oil, and vanilla until completely smooth.

   Pour the wet ingredients into the dry ingredients and whisk just until no dry streaks of flour remain.

4. Finish batter with espresso

   Slowly pour in the hot espresso while whisking, mixing until the batter is glossy and fairly thin.

5. Bake the chocolate cakes

   Divide the batter evenly between the prepared pans and smooth the tops with a spatula.

   Bake for 24 to 28 minutes, until the centers spring back and a tester comes out with a few moist crumbs.

6. Cool the cake layers

   Let the cakes cool in their pans for 10 minutes on a wire rack.

   Turn out the layers, peel off the parchment, and cool completely before assembling.

7. Bloom the gelatin

   Place the powdered gelatin in a small bowl and sprinkle 1 tablespoon cold water over it.

   Let stand for at least 5 minutes, until the gelatin absorbs the water and looks thick and spongy.

8. Cook the lemon custard base

   In a medium saucepan whisk the egg yolks, sugar, and cornstarch until the mixture looks pale and slightly thick.

   Whisk in the milk and heavy cream until fully combined and no cornstarch lumps remain.

   Cook over medium heat, whisking constantly, until the custard starts to bubble and feels noticeably thick.

9. Thicken and chill the custard

   Remove the saucepan from the heat and whisk in the bloomed gelatin until it fully dissolves.

   Whisk in the lemon juice, lemon zest, and butter until the custard is smooth and silky.

   Transfer the custard to a shallow dish, press plastic wrap directly on the surface, and chill until thick but spreadable.

   Plan for about 1 to 2 hours of chilling time in the refrigerator.

10. Level and prepare the cake layers

    If the cake tops are domed, trim them level with a long serrated knife once completely cool.

    Place one layer on a serving plate or cake stand and secure it with a small dab of custard.

11. Assemble the cake

    Spread about half of the lemon custard over the first layer, pushing it gently to the edges.

    Set the second cake layer on top, cut side down, and press very lightly to create an even sandwich.

    Spread a thin layer of the remaining custard over the top, using an offset spatula for smooth coverage.

12. Chill the assembled cake

    Refrigerate the filled cake for at least 1 hour so the custard firms and the slices hold neatly.

13. Add cocoa and lemon topping

    Right before serving, dust the top generously with cocoa powder using a fine-mesh sieve.

    Finish with fresh lemon zest for color and a bright citrus aroma.