Easy Method #1: Peel and squeeze water and seeds from tomatoes, or crush through a food mill to remove seeds and skin. Puree in a blender or in a pot, with a stick blender, or simply crush by hand with a potato masher for a chunkier sauce. Set crushed tomatoes aside.
Add 2 tbsp olive oil to a large stockpot, then sauté onion and garlic. Add tomatoes and remaining ingredients* to the pot and simmer together for at least one hour or longer for the desired consistency.
Easy Method #2: Cut tomatoes in half. Sprinkle olive oil on the bottom of a baking dish, and place tomatoes cut side up in dish. Add garlic and onion between tomatoes, and sprinkle with chopped herbs, salt, and pepper. Roast in oven at 300 degrees for about 45 minutes, until the tomatoes have given up most of their water and are soft. Scrape vegetables into a blender and pureee or use a potato masher to combine roasted vegetables and mash into a chunkier sauce.
This sauce is perfect for freezing in airtight containers, plastic zipped bags, or canning in glass jars (just add 1 tbsp lemon juice and 1 tsp sugar to per pint jar).
* Feel free to add various herbs like oregano, rosemary, thyme, or bay leaves for a more flavorful sauce.