Blueberry Cake

Cooking method

1. Step 1:

   

   How do you make blueberry cake? Measure out the ingredients for a classic sponge cake. I recommend splitting the amounts in two and baking two sponges, so the berries are more evenly spread through the cake. You can use potato starch instead of corn starch. Wash the blueberries ahead of time and dry them thoroughly — the berries shouldn't be wet.

2. Step 2:

   

   Mix the flour with the starch and vanillin and sift. The flour gets aerated, making the sponge airier and more porous.

3. Step 3:

   

   Carefully separate the eggs into whites and yolks. Not a drop of yolk should get into the whites, or you won't be able to whip a stable meringue.

4. Step 4:

   

   Beat the yolks on high speed with half the sugar (about 40 g) to a thick, pale mass.

5. Step 5:

   

   In a dry, clean, grease-free bowl, whip the whites. Start on low speed until they thicken slightly. Without stopping, add the remaining sugar in small batches. Gradually raise the speed to maximum. Whip the whites to a stable, firm foam.

6. Step 6:

   

   Using a spatula, gradually fold the whipped whites into the yolk mixture. Do it very gently with scooping motions from the bottom up, so you don't knock the air out of the whites.

7. Step 7:

   

   Add the lemon zest.

8. Step 8:

   

   Add the flour mixture in small batches, gently folding with the spatula from the bottom up. Work carefully but don't drag it out.

9. Step 9:

   

   The batter comes out airy and smooth.

10. Step 10:

    

    Line the bottom of the baking pan with parchment. The sides don't need greasing. Gently pour the batter into the pan. Scatter the blueberries evenly over the top, pressing them slightly into the batter. My pan is 8 inches (20 cm) across. If you have two identical pans, you can bake the sponges at the same time; if not, one after the other.

11. Step 11:

    

    Bake the sponge in an oven preheated to 300–325°F (150–160°C) until lightly golden, about 30 minutes. Don't open the oven while it bakes, or the temperature change may make the sponge collapse. Leave the sponge in the turned-off oven with the door ajar for 10 minutes, then take it out. The setting and time may differ — go by your own oven. Cool the finished sponge a little and turn it out of the pan. It comes out very tender.

12. Step 12:

    

    Make the second sponge the same way. The finished sponges should cool completely.

13. Step 13:

    

    Meanwhile, make the lemon curd. It's best to take the ingredients out ahead of time so they come to room temperature. Wash the lemons and dry them well.

14. Step 14:

    

    Zest the lemons and squeeze the juice. I got about 120 ml (1/2 cup) of lemon juice.

15. Step 15:

    

    Rub the zest well into the sugar so it releases its aroma.

16. Step 16:

    

    Beat the eggs with a fork or whisk until smooth.

17. Step 17:

    

    In a small heavy-bottomed saucepan, combine the sugar-and-zest with the lemon juice. Mix well.

18. Step 18:

    

    Add the beaten eggs and stir.

19. Step 19:

    

    Set the saucepan over low heat. Stirring the whole time (!), cook the lemon mixture until it thickens. If you're worried the eggs might curdle, you can cook the curd in a water bath. To check the curd, draw a line across the spatula you stirred it with — if it leaves a clear track, the curd is ready.

20. Step 20:

    

    Strain the curd through a sieve to remove the lemon zest.

21. Step 21:

    

    Add the soft butter to the warm curd and mix well until smooth.

22. Step 22:

    

    To keep a skin from forming on top, press plastic wrap directly onto the curd's surface. Chill the curd well.

23. Step 23:

    

    I cut each sponge in two. If you bake in a 9–10 inch (22–24 cm) pan, the layers will be thinner and you can leave them whole.

24. Step 24:

    

    For the cream, the cream must be well chilled. Chill the mixing bowl too.

25. Step 25:

    

    Start whipping the cream on low speed. Add the vanilla sugar. Gradually adding the powdered sugar and raising the speed, whip the cream until thick. When the beaters leave visible, fairly firm marks, stop whipping.

26. Step 26:

    

    Add the mascarpone to the cream.

27. Step 27:

    

    Mix on low speed until smooth. The cream is ready.

28. Step 28:

    

    Start assembling the cake. I lined the plate with strips of parchment to keep it clean while building the cake, but that's optional. Spread a sponge layer with lemon curd.

29. Step 29:

    

    Spread the cream on top.

30. Step 30:

    

    Cover with the next layer and spread with curd again.

31. Step 31:

    

    Repeating the steps, build the whole cake. Cover the top and sides with cream. Refrigerate the dessert for 5 to 6 hours so it soaks and grows more flavorful.

32. Step 32:

    

    Before serving, decorate the cake with blueberries or however you like, cut into portions, and serve. Enjoy!