Preheat oven to 325°F. Line an 8x8-inch baking pan with parchment paper. Set aside.
With a hand mixer, whip the egg whites in a large bowl until stiff peaks form. Set aside.
4 large eggs
In a separate bowl, beat the egg yolks and sugar until the mixture turns a pale yellow color.
1½ cup granulated
Stir in the butter, vanilla extract, and salt. Gradually add the flour and stir just until combined.
½ cup unsalted butter, 1½ teaspoons pure vanilla extract, ⅛ teaspoon kosher salt, 1½ cups all-purpose flour
Add the milk and stir once again, then gently fold in the beaten egg whites until smooth but still slightly lumpy. Be careful not to deflate the egg whites.
2¼ cups milk
Pour the batter into the prepared baking pan and bake for 40-50 minutes, or until the center of the cake only jiggles slightly.
Let the cake cool for 2 hours before dusting the top with some powdered sugar and slicing and serving with berries if desired.
Powdered sugar
Notes
Make sure to separate your egg whites from the egg yolks before you mix them.
Bake the cake for a minimum of 40 minutes. The center of it should jiggle a bit when you remove it.
You can serve this Magic Custard Cake with fresh berries that pair perfectly with it.
Nutritional information does not include optional ingredients.
Storage: Store magic cake in an airtight container in the refrigerator for up to 5 days.