Start by preparing the spaghetti squash. Use a fork to poke a few holes in the spaghetti squash where you will cut the it in half (length wise). Microwave the entire squash for about 5 minutes. Use a large, sharp knife to cut the squash in half. Use a spoon to scoop out the seeds. Spray each half of the spaghetti squash with cooking oil (or drizzle with olive oil). Sprinkle each side with salt and pepper. Place the spaghetti squash halves face side down on a greased baking sheet. Bake at 400 for 30-40 mins until tender and lightly brown. Take the squash out of the oven, let cool, and use forks to shred the squash into strands. Place the shredded squash in a bowl and set aside.
Heat a large skillet over medium-high heat. Add olive oil.
Add the pepper, onion, garlic, and ground turkey to the skillet. Sprinkle with seasonings. Cook for about 10 minutes, until the meat is no longer pink.
Add the can of tomatoes to the skillet. Cook for another 3-5 minutes.
Scoop in the spaghetti squash and ½ of the cheese. Mix well.
Use a slotted spoon or tongs to add the casserole mixture to a greased casserole dish. (The slotted spoon is to leave behind the juices. Adding some of the juice is no big deal.)
Sprinkle remaining cheese on top of the casserole.
Bake at 350 for 20 minutes or the cheese is melted.
Top with additional red pepper flakes for a kick. Enjoy!