Preheat the oven at 400 degrees
First of all, it is important to preheat the oven at 400 degrees while you prepare the rest of the stuff.
Chop the onion, garlic and tomatoes
In the meantime, you can chop the ingredients like the onion, garlic clove and the tomatoes, but don’t mix them in one bowl.
Make the spaghetti squash hollow
Cut the spaghetti squash into half and make it hollow, using a spoon. Once it is done, sprinkle some salt and oil over it.
Put the squash on a cookie sheet facing down
It is important to put the squash face down on the cookie sheet before putting it in the oven.
Heat the squash in the oven for 40 minutes
Put the spaghetti squash in the oven and heat it for 40 minutes. It will be ready to be served now.
Make the sauce
Finally, prepare the sauce in a pan, mixing the chopped onion, tomatoes and garlic clove. Now you can pour it over the spaghetti to serve it.