Speghetti Squash with Fresh Tomato Sauce

This is one of my favorite meals. It's very light and healthy.
Ingredients;
1 large speghetti squash
3 Tbsp olive oil
1medium onion, minced
1/2 tsp crushed red pepper
1 large clove of garlic, minced
1 sprig of fresh rosemary
1/2 of a 28 oz can of crushed tomatoes
Sea salt and pepper to taste
12 fresh basil leaves, thinly sliced
Cut speghetti squash in half. Wrap both halves in foil and bake in oven at 435.
Meanwhile heat oil in skillet. Add onion and pepper flakes. Cook until onion is soft. Add garlic, continue cooking for another 2 minutes.
Add all other ingredients and simmer for 20 minutes.
When squash is cooked, remove from oven. Scoop seeds and discard.
Run tines of fork lengthwise over surface of squash to loosen speghetti like strands; scoop out strands.
Add speghetti squash to the sauce and serve.