Fluffy sponge cake with pastry cream, decorated with cake crumbles resembling mimosa flowers, celebrates International Women's Day. This festive mediterranean dessert is an Italian family tradition each March 8th.
Preheat the oven to 350°F. Line two 8-inch round cake pans with parchment and lightly butter the sides.
Separate 6 eggs, placing the yolks and whites in separate mixing bowls. Beat the yolks with 3/4 cup of sugar until pale and thick. Add lemon zest.
In another bowl, whip the egg whites with 1/4 cup sugar and a pinch of salt to stiff peaks. Gently fold into the yolk mixture.
Sift together the flour and cornstarch, then fold gently into the egg mixture in batches to maintain the batter’s volume.
Pour the batter evenly between pans, smooth the tops, and bake for 22–25 minutes until golden and springy. Cool completely, then level the cakes. Reserve one cake for mimosa topping by crumbling it.
For pastry cream, heat whole milk with vanilla in a saucepan until steaming. Separately, whisk 3 egg yolks (from reserved), 1/3 cup sugar, and 2 tbsp cornstarch until smooth, then temper with hot milk. Return to pan, whisking over medium-low until thick, then whisk in 2 tbsp butter. Cool to room temperature, then gently fold in whipped heavy cream.
To assemble, slice one cake into two layers. Spread a generous layer of pastry cream between the layers and on top.
Press crumbled sponge cake onto the pastry cream, covering completely to mimic mimosa flowers. Sift powdered sugar decoratively over the top.
Chill assembled cake at least 2 hours before serving for best texture and clean slicing. Serve cold.