If your skillet is not ovensafe, prepare the recipe through step 3 and then transfer the filling to a 13 by 9-inch baking dish. Top the filling as directed and bake for an additional 5 minutes. We like Golden Delicious apples for this recipe, but any sweet, crisp apple such as Honeycrisp or Braeburn can be substituted. Do not use Granny Smith apples in this recipe. While rolled oats are preferable in the topping, quick-cooking oats can be substituted. Serve the apple crisp warm or at room temperature with vanilla ice cream or whipped cream.