1. Preheat oven to 375F. Grease an 8-inch square baking dish. Layer apple over bottom of prepared dish.
2. Combine brown sugar, cinnamon and nutmeg in a shallow bowl; mix well.
3. Separate biscuits. Coat biscuits on all sides in brown sugar mixture.
4. Arrange biscuits over apple in baking dish. Sprinkle any remaining brown sugar over biscuits. Drizzle with butter. Bake until buns are golden, about 25 minutes. Serve buns apple-side up.