Toss in butternut squash spirals, spinach, onions, garlic clove, thyme, rosemary, salt and pepper together.
In a casserole pan, add in half of the butternut squash spirals. Top with parmesan cheese. Add remaining butternut squash spirals. Top casserole dish with all the cheddar cheese.
Bake for 22-25 minutes until squash is soft.
Remove from oven and let cool. Top with more cheddar, thyme and rosemary if desired.Enjoy!