In a microwave save dish, place your squash halves side by side. Add about 1/4 cup water to the bottom of the dish (water should be covering the bottom, but not more than 1/4 inch high). Place into microwave and cook on high for 9-11 minutes, or until squash is tender** Remove, and set aside for about 10 minutes to cool.
In a skillet coated with nonstick spray, add red pepper flakes and cook for 30 seconds, stirring constantly. Add broccoli and garlic, stirring to combine. Add about 2 TBS water to the skillet, and turn up the heat. Saute for 3-5 more minutes, or until the chopped broccoli is tender. Add mixture to a large bowl, discarding any left over water.
Using a fork, scrape out the flesh/'spaghetti' of the squash, and add it to the large bowl with the broccoli mixture. Add Parmesan cheese, salt and pepper, and Italian seasoning to the mixture, stir to combine.
Turn your broiler on medium/high. Distribute the mixture back into the squash shells, then sprinkle 1/4 cup of mozzarella cheese on top of each squash half. Place shells into an oven safe baking dish/pan.
Place under broiler, watching carefully. Remove when cheese is bubbling and browned, about 2-3 minutes depending on how close the squash is to the broiler.
Remove and enjoy!
**You can also cook in the oven - Place into a 350 degree oven on a baking sheet, flesh side down, cook for 50-60 minutes, or until squash is tender.