Italian Zucchini Casserole

A cheesy, Italian-seasoned zucchini casserole that turns piles of summer squash into a satisfying main dish or side. Blanched zucchini rounds get topped with a quick sauce made from spaghetti seasoning mix, tomato paste, cheddar cheese, and mushrooms, then finished with a shower of Parmesan and baked until bubbly.

Blanching the zucchini first for 4-5 minutes softens it just enough so it finishes cooking in the oven without releasing a flood of water into the casserole. Raw zucchini in a bake often turns waterlogged, but this par-cooking step draws out some of the moisture first.

The spaghetti sauce mix dissolved in water and tomato paste creates a concentrated, well-seasoned sauce without needing to simmer anything for a long time. Cheddar melts into it and the mushrooms add an earthy bite.

Pro Tips

• Drain the blanched zucchini well. Shake it in a colander and even blot with a towel. Excess water is the enemy of a good casserole.
• Saute the onion and green pepper until soft before building the sauce. Raw aromatics taste harsh in a quick-baked casserole.
• Let it rest 5-10 minutes after baking before serving. The sauce thickens as it cools slightly and the slices hold together better.

Variations

• Use fresh sliced mushrooms instead of canned and saute them with the onion for a richer flavor.
• Add Italian sausage or ground beef to the sauce for a heartier, non-vegetarian version.
• Swap cheddar for mozzarella and add fresh basil for a more traditional Italian flavor profile.