This recipe calls for cooked winter squash.

2 c sliced leeks, white and light green parts only, or 2 c sliced onion
1-1/2 t fresh thyme leaves, or 1/2 t dried thyme
2 T vegetable oil
2-1/2 c thinly sliced apples
1 T flour
1-1/2 c grated cheddar cheese
2 T bread crumbs
3 c cooked, lightly mashed winter squash
salt and pepper, to taste

1. Preheat the oven to 350ºF. Grease an 8-inch by 8-inch (2 quart) baking dish.

2. Gently sauté the leeks or onion and thyme in the oil for about 20 minutes, or until the onion is soft and golden. Meanwhile, toss the apple slices with the flour, and in a separate bowl, the cheddar cheese with the bread crumbs.

3. Put the cooked, mashed squash in the prepared baking dish–smooth it out. Sprinkle with salt and pepper, if desired. Next add the onions in a layer. Over the onions layer the apples slices. Add some more salt and pepper. Sprinkle the cheddar-bread crumbs mixture on top.

4. Cover with foil and bake for 30 minutes, then uncover and bake for 15 more minutes. The apples should be tender and the topping bubbly and golden.