Preheat oven to 180ºC . Combine hazelnuts, flour, baking powder and sugar. Add egg, butter, milk, vanilla, salt and apples. Let stand 10 minutes. Fill 4 cups of a nonstick muffin pan (or regular muffin pan with paper liners) with the batter. Bake 8 to 10 minutes, until a toothpick inserted in the center comes out clean. From the cookbook "Apples" by Robert Berkley