For the blueberry pancakes, separate the egg. In a bowl, mix flour, yolks, sugar, salt and milk until well blended and let rest for 1/2 hr. Allow the blueberries to thaw, if frozen.
Beat the egg whites until stiff and fold into the batter after resting. Melt the butter in a coated pan, pour in the batter and spread the blueberries on top.
Bake over low heat until the surface is no longer runny, then turn over and finish baking.
Dust with powdered sugar.