Beat together ricotta, egg yolks, sugar, flour and vanilla in mixing bowl. Fold in beaten egg whites.
Heat greased griddle or skillet over medium heat or to 375°F (190°C). Griddle is ready when a few drops of water bubble and skitter rapidly around.
For each pancake, pour scant 1/4 cup batter onto hot griddle. Cook pancakes until puffed, bubbly and dry around edges. Turn and cook other sides until golden brown. Serve with fresh fruit such as raspberries, blackberries or strawberries macerated with sugar.