In a medium bowl whisk eggs yolks, lemon zest, sugar, salt, ricotta cheese, and flour. In a separate bowl beat egg whites with an electric mixer until they form slightly stiff peaks.
Fold eggs whites into ricotta/flour mixture until well blended.
Add a little bit of butter to a skillet or griddle over medium-high heat. Spoon batter into the pan to form a pancake of the desired size you want.
Cook for 1 minute or until the top starts to bubble and/or the bottom is golden brown, flip the pancake onto its other side and cook until the pancake is cooked thoroughly throughout (About 1- 1 1/2 minutes).