Preheat the oven to 400°F. Cut the spaghetti squash in half and stand them up on a small baking sheet. Spray the tops with zero-calorie nonstick cooking spray and sprinkle with salt and pepper.
Bake for 45 minutes, then remove from the oven to cool.
While the squash is in the oven, prepare the meat sauce filling. Spray zero-calorie nonstick cooking in the pan/pot over medium heat, and once hot, add the diced onions and carrots. Stir and let cook for about 6 to 7 minutes until the onions and carrots start to cook down.
Add the garlic, ground meat, Italian seasoning, and a pinch of salt. Stir and let cook until the meat is cooked, then add the jar of marinara sauce.
Turn heat to low, cover, and cook for 15 minutes, then remove from heat.
Use a fork to separate the spaghetti squash and fill each bowl with meat sauce. Add freshly grated parmesan cheese and chopped basil, and enjoy.