Preheat the oven to 400°F. Grease the cups of 2 mini-muffin tins and set aside. Cream the butter and brown and granulated sugars. Add the beaten egg yolks, flour, baking powder and 2 tablespoons of the cherry juice, blending well. Fold in the egg whites. Sprinkle ¼ teaspoon of chopped nuts in the bottom of each muffin cup. Spoon in 1 teaspoon of batter, then place half a cherry in the center of the batter. Drop another teaspoon of batter on top. Sprinkle a few chopped nuts on top of each muffin. Bake for 10 minutes, then remove from the tins and dust with powdered sugar while hot.