Separate the egg whites and yolks into two mixing bowls. In the bowl with yolks, whisk together milk, vanilla extract, and optional lemon zest until combined. Sift in flour and baking powder, mixing gently until smooth.

In a clean bowl, beat the egg whites with vinegar or lemon juice until frothy. Gradually add sugar while whisking until stiff peaks form, about 3-5 minutes.

Gently fold one-third of the meringue into the yolk mixture using a spatula, then incorporate the remaining meringue carefully.

Preheat a greased nonstick pan over low heat, ensuring the temperature stays between 285°F and 320°F. Cover with a lid to maintain humidity.

Spoon the batter into the pan to form mounds, cover, and let cook for 7-8 minutes. Once golden brown underneath, flip the pancakes and cook for an additional 5-6 minutes.

Serve immediately topped with your favorite ingredients.