Mix all the ingredients except the egg whites.
Beat the egg whites until they form stiff peaks.
Fold in the egg whites.
Heat the pan and add a little butter into each hollow.
Fill each cup 3/4 full of batter or 1/2 full if adding in a filling (add in a dollop of filling) and then top with more batter.
As soon as they get bubbly around the edges flip them using a knitting needle or chopsticks.
Continue cooking and turning until they are cooked through and a golden brown.
Remove and sprinkle with powdered sugar.
Serve warm with coffee