Separate the eggs. Beat the egg yolks with the sugar and beat the egg whites until stiff. Mix the flour with the baking powder and sieve. Gradually add the flour-baking powder mixture and the mineral water to the egg yolk. Add enough mineral water while stirring until a creamy, foamy dough is formed. Let the dough rise in the refrigerator for at least 30 minutes.
Take the batter out of the refrigerator, fold in the egg whites and add the drained peach wedges.
Heat a pan and melt some butter in it. Put a ladle of batter in the pan and bake the batter until golden brown on both sides. Repeat the process until the batter is used up.