Preheat oven to 350°F. Grease an 8x8-inch baking dish.
Place ½ lb Italian sausage in a large skillet and cook until browned, breaking up the sausage as it cooks (remove the casings if you started with sausage links). Remove the sausage from the pan with a slotted spoon, leaving the drippings.
Place the sausage into the baking dish and stir in 1 tablespoon flour.
Add 3 cups diced zucchini and ½ small onion (diced) to the skillet and cook just until tender. Toss with the remaining flour. Spoon half the zucchini over the meat.
In a medium bowl, whisk together 1 cup cottage cheese, ¼ cup parmesan cheese, and 1 egg. Pour over the zucchini layer, and top with the remaining zucchini mixture. Sprinkle ¾ cup shredded cheddar over the top.
Bake for 15–20 minutes, or until heated through.
Notes
I'm usually wary of recipes that don't contain salt, but there's no need for any additional salt here. There's salt in both the Italian sausage and the cheeses, so the dish is nicely seasoned already.Leftovers keep nicely in the fridge for several days. Reheat in the oven or microwave. Variations:
Sauté some mushrooms with the zucchini
Add a tablespoon or two of fresh herbs like basil or parsley
Add a couple cloves of minced garlic (sauté with the zucchini)
For a little zip, use spicy Italian sausage or add red pepper flakes