Preheat the oven to 180 degrees. Grease the recesses in the muffin sheet or put paper baking cases in them.
Drain the peach halves in a colander and cut into small pieces.
Wash fresh fruits, cut in half, remove the stones and cut the peaches into pieces. Sift the flour into a bowl and mix carefully with the whole wheat flour, baking powder, baking soda and cinnamon. In a second, large bowl, crack open the egg and whisk gently. Then add sugar, oil, sour cream or buttermilk, bitter almond extract or 1 tablespoon whiskey and stir well. Add the flour mixture and stir in briefly.
Finally, carefully fold in the peaches.
Pour the batter into the tray. Sprinkle 1 teaspoon of brown sugar on each.
Bake in the oven (center, fan oven 160 degrees) for 20-25 minutes.
Let the muffins rest in the baking tray for about 5 minutes, remove them from the molds and serve warm.
Make sure to stir the dough only briefly so that the muffins are nice and loose.