For a richer flavor, use brown butter instead of regular butter. Simply melt the butter in a saucepan over medium heat, swirling occasionally, until it turns golden brown and smells nutty. Let it cool slightly before using. Feel free to experiment with different apple varieties. Honeycrisp, Gala, or Fuji apples work particularly well in this recipe. A sprinkle of chopped walnuts or pecans adds a nice textural contrast and nutty flavor. Leftovers can be stored in an airtight container in the refrigerator for up to 3 days. Reheat gently in the microwave or oven before serving.