Step 1

Preheat oven to 375 degrees F. Slice the squash in half lengthwise and scoop out the seeds. Place in a shallow baking dish, cut-side down, and then pour 1/2 cup water into the dish, around the squash. Bake for 35 to 40 minutes, until the flesh of the squash is easily pierced with a fork. When cool enough to handle, pull the squash strings out of the squash's center with a fork and transfer to a large mixing bowl. The squash strings should look like spaghetti.

Step 2

Reduce the oven temperature to 350 degrees F. Heat the olive oil in a large, deep skillet over medium high. Add the turkey, onion, bell pepper, salt, and black pepper. Cook, breaking apart the meat, until meat is browned and the vegetables are tender, about 8 minutes. Add the drained tomatoes, garlic, Italian seasoning, and red pepper flakes. Let cook until most of the liquid from the tomatoes has cooked off, about 4 minutes, and then add the reserved squash. Cook and stir until most of the remaining liquid has cooked off, about 1 to 2 minutes more, increasing the heat if needed. Stir in 1/2 cup of the shredded cheese. There may be some liquid remaining in the pan.

Step 3

Lightly coat a deep 8x8-inch baking dish or 2-quart casserole dish with nonstick spray. With a slotted spoon, scoop the squash mixture into the pan in an even layer, discarding any excess liquid (some in the pan is OK—just not too much). Bake, uncovered, for 20 minutes. Remove from the oven and sprinkle with the remaining 1/2 cup cheese, and then return to the oven and bake until the cheese melts, about 5 to 10 additional minutes. For an extra-golden-brown top, place the casserole under the broiler for a few minutes. Remove from the oven, sprinkle with parsley and/or basil, and let rest 5 minutes. Serve hot.