Ingredients:
- 1 cup (120g) cake flour, sifted
- 1 1/2 cups (300g) granulated sugar, divided
- 1/4 teaspoon salt
- 10 large egg whites (about 1 1/4 cups or 300ml), at room temperature
- 1 teaspoon cream of tartar
- 1 teaspoon pure vanilla extract
- 1 cup (240ml) fresh lemon juice (about 4-6 lemons)
- 1 cup (200g) granulated sugar
- 3 large eggs
- 1/4 cup (30g) cornstarch
- 1/4 teaspoon salt
- 4 tablespoons (56g) unsalted butter, cut into pieces
- Zest of 2 lemons
Instructions:
- Preheat oven to 350°F (175°C).
- In a bowl, sift together flour, 3/4 cup sugar, and salt.
- In a separate bowl, whisk egg whites until foamy.
- Add cream of tartar and continue whisking until soft peaks form.
- Gradually add remaining sugar, beating until stiff peaks form.
- Gently fold in flour mixture and vanilla until just combined.
- Pour into an ungreased angel food cake pan and smooth the top.
- Bake for 30 minutes until golden brown. Invert pan to cool.
- In a medium saucepan, combine lemon juice, sugar, eggs, cornstarch, and salt.
- Whisk until smooth and cook over medium heat until thickened (about 5-7 minutes).
- Remove from heat, add butter and lemon zest, stir until well combined.
- Transfer to a bowl and cover with plastic wrap directly on the surface to prevent a skin. Chill for at least 30 minutes.
- Once both components are cool, carefully remove the angel food cake from the pan.
- Slice the cake into layers or keep whole, depending on preference.
- Spoon lemon filling over the cake or layer it between slices.
- Serve immediately or chill until serving.