Now, let’s dive into the process of bringing this cake to life. Each step is crafted to ensure you achieve a perfect bake, drawing from the lessons I’ve learned from countless afternoons spent experimenting in my kitchen.

1. Preheat your oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan.
2. In a large bowl, cream together the softened butter and sugar until the mixture is light and fluffy, about 3-4 minutes. This was a step my abuela always emphasized — the secret to airy cakes.
3. Add the vanilla extract to the creamed mixture, blending it in thoroughly.
4. In a separate bowl, sift together the flour, baking powder, and salt.
5. Gradually add the dry ingredients to the creamed mixture, alternating with the milk. Begin and end with the flour mixture, mixing just until combined. Over-mixing can lead to a denser cake, a tip passed down from my family kitchen.
6. In another clean bowl, beat the egg whites until stiff peaks form. Gently fold the beaten egg whites into the batter, ensuring you maintain the airy texture.
7. Pour the batter into the prepared baking pan, smoothing the top with a spatula.
8. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Let the cake cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.