Creating the wonderful Cloud Cake is simple when you follow these detailed steps:

1. Preheat the Oven: Start by preheating your oven to 350°F (175°C). Grease and flour an 8-inch round cake pan.
2. Separate the Eggs: Carefully separate the egg yolks from the egg whites. Place them in different mixing bowls.
3. Mix Egg Yolks and Sugar: In the bowl with the yolks, add granulated sugar. Beat until the mixture turns light and fluffy.
4. Add Milk and Flavor: Gradually stir in the whole milk and vanilla extract. If using lemon juice, add it here as well. Mix until combined.
5. Sift in Dry Ingredients: In a separate bowl, sift the flour, baking powder, and salt together. Gradually fold this mixture into the wet ingredients.
6. Beat Egg Whites: In the bowl with the egg whites, beat them until soft peaks form. This adds that incredible fluffiness to your cake.
7. Combine Mixtures: Gently fold the beaten egg whites into the batter. Be careful not to deflate the mixture; the airiness is key!
8. Pour Batter into Pan: Pour the cake batter into the prepared pan, smoothing the top as needed.
9. Bake: Place in the oven and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.
10. Cool the Cake: Once baked, remove from the oven and let it cool in the pan for about 15 minutes. Then carefully transfer it to a wire rack to cool completely.

With these steps, your Cloud Cake will come out fluffy and perfect!