Squash and Spinach Gratin

Ingredients:
3 pounds fresh spinach, stems discarded, or 3 (10-ounce) packages frozen leaf spinach, thawed3/4 cup finely chopped onion (1 small)
3 garlic cloves, minced
1 1/2 teaspoons salt
3/4 teaspoon black pepper
Rounded 1/2 teaspoon freshly grated nutmeg
1 cup heavy cream
3 yellow squash sliced
2 tomatoes
Mozarella Cheese for topping
1 tbls. butter
oil

Directions:
Preheat oven: 400 F.
Saute onions and garlic in oil until onions are translucent.
Place in bowl with spinach.  Mix in nutmeg, salt, pepper and cream.
Grease bottom of a pan (I've used a loaf pan and a springform pan for this).
Cut up half of the butter and place on bottom of pan.
Line with slices of yellow squash.
Layer with spinach mixture and repeat.
On the top layers, place sliced tomatoes, remaining butter and cheese.
Bake for 40 min.

Recipe modified from here.