Tres Leches Cake (Three Milks Cake)

Preheat the oven to 350 degrees F (175 degrees C). Grease and flour an 8x12-inch baking dish.

Separate 5 eggs. Beat egg whites in a large bowl. Add 1 cup sugar slowly to egg whites, beating constantly. Add yolks one at a time, beating well after each addition. Stir in 1 teaspoon vanilla. Sift flour over egg mixture and stir until well combined. Pour batter into the prepared baking dish.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 20 minutess. Allow to cool completely.