SERVES 20:

SPONGE CAKE:
5 pounds (2.2kg) granulated sugar
27 eggs 
1½ quarts (1.35l) milk 
4 pounds (1.89kg) all-purpose flour
6 tablespoons (90g) baking powder 

STRAWBERRY JAM FILLING:
1 pound (500g) strawberries, fresh or frozen
1 cup (200g) granulated sugar
2 tablespoons (30ml) lemon juice 

VANILLA CREAM FILLING:
2¾ cups (670ml) milk 
3 egg yolks 
¾ cup (170g) granulated sugar
3 tablespoons (30g) cornstarch 
Seeds scraped from 1 vanilla bean
½ cup (100g) butter, at room temperature 

LEMON CREAM CHEESE FROSTING:
1 pound (540g) cream cheese, at room temperature
1 cup (225g) butter, at room temperature
2/5 cups (270g) powdered sugar
1½ tablespoons (9g) lemon zest 
3 tablespoons (45ml) lemon juice 

FOR DECORATION:
Edible flowers
Edible silver balls

STEP ONE: 
SPONGE CAKE

— Preheat the oven to 350°F (175°C). Grease and line three large, rimmed baking sheets with parchment paper.

— In a very large mixing bowl, beat the sugar and eggs together until the mixture is light and fluffy. Gradually add the milk, mixing well until combined.

—  In a separate large mixing bowl, sift together the flour and baking powder.

—  Gradually fold the dry ingredients into the wet mixture, stirring gently until smooth and well combined.

— Spread the batter evenly across the prepared baking sheets, making sure the layers are around ½ inch thick (between 1 and 2 cm).

—  Bake in batches for 20 to 25 minutes, or until a toothpick inserted in the center of the cakes comes out clean. Keep an eye on them to avoid overbaking.

— Once baked, remove from the oven and let cool in the trays for about 10 minutes. Transfer them to wire racks to cool completely.

STEP TWO 
STRAWBERRY JAM FILLING

— In a large saucepan, mash the strawberries with a potato masher.

— Add the sugar and lemon juice, then bring to a boil.

— Cook over medium-high heat, stirring occasionally, for about 15 to 20 minutes or until the mixture thickens.

— Remove the mixture from heat and let it cool completely.