Place all veggies, onion through parsley, into a food processor. Pulse until all veggies are ground to a fine consistency.
In a wide sauce pan or high-sided sauté pan (I use a 6qt sauté pan), heat olive oil over medium heat. Add the veggie mix and cook, stirring occasionally, for 10 minutes.
Add tomato paste and salt, sauté 5 minutes more.
Add strained tomatoes, reduce heat to low and simmer for 20 minutes.
Add oregano and continue to simmer for 10 minutes.
Serve with pasta or polenta or whatever strikes your fancy. Enjoy!