My family devoured this casserole – it was gone in minutes

Ingredients:

1 container penne (16 oz)
1 container frozen chopped spinach (10 oz) or 1 lb fresh chopped spinach
1 cup crumbled feta cheese
1/4 cup chopped fresh dill (or 3 teaspoons dried dill)
1 container ricotta cheese (15 oz)
8-ounce shredded mozzarella cheese
Salt and pepper to taste