Add the oil to a pan and heat on medium-low until shimmering. Add sausage and brown, adding the onion when the sausage is almost finished browning.
Add tomatoes, zucchini, and garlic and cook for about 3 minutes, lightly mashing the tomatoes as they cook.
Add the can of pureed tomatoes and simmer for 5-7 minutes.
Toss with herbs and pasta or spaghetti squash.
This recipe really compliments the flavor of spaghetti squash - I love using it in place of regular pasta. To bake spaghetti squash: Heat oven to 400. Cut squash in half lengthwise. Scrape out seeds. Drizzle inside with olive oil and sprinkle with salt and pepper. Bake 35-40 minutes until tender.