Mix egg whites with an electric mixer until they are stiff (about four minutes). Set aside.

Combine flour, baking powder, salt, and sugar.

Roll lemons and press down to break up the pulp inside the lemons to get more juice from each lemon.

Zest each lemon.

Add egg yolks, milk, lemon juice, lemon zest and melted butter to the flour mixture. MIx until just blended.

Carefully fold in egg whites until blended.

Cook on a hot waffle iron until light to golden brown.

Top with lemon or vanilla Greek yogurt, cut up strawberries and blueberries.