Combine egg yolks, ricotta, sugar, flour and lemon zest in electric mixer until smooth.
In a separate mixing bowl, whip egg whites into stiff peaks (you can use the electric mixer here too).
Add the egg whites to the yolk mixture by gently folding in.
Heat a skillet over medium heat and add a small amount of butter. Ladle a spoonful of batter into the pan and cook until it begins to bubble on the top. Flip and cook the other side. Serve immediately with blueberries and whipping cream.