Zucchini Pasta Casserole

1 pound lean ground beef
1 1/2 cups sliced onions
2 cups unpeeled, diced zucchini
2 teaspoons finely chopped fresh garlic
2 (28 ounce) cans stewed or diced tomatoes with juice, chopped
4 tablespoons soy sauce
1 teaspoon crushed red pepper flakes
4 cups spiral-shaped pasta
2 cups shredded Cheddar cheese

Preheat oven to 375 degrees F. Grease a large deep ovenproof casserole dish.

Brown meat with onions, zucchini and garlic. Cook until meat is done and vegetables are soft. Drain fat. Mix in dry pasta.

In another bowl mix tomatoes and their juice, soy sauce and red pepper flakes. Mix into beef mixture. Put mixture into prepared dish, ensuring that the pasta is submerged in the liquid. Bake, covered, for 20 minutes.

Remove cover, lower oven to 350 degrees F, sprinkle with cheese and return to oven, uncovered, for another 20 minutes.