Ok--I make my own spaghetti/marinara sauce in about 5 min. but it tastes so good so I'll list it. I'm just thinking about it because I used it in my chicken parmigiana last night and got many compliments.
4-5 garlic cloves
Crushed red pepper
Fresh Italian parsley (a handful chopped)
1 14 oz. can chunky crushed tomatoes
1 28 oz. can crushed tomatoes in their juices (usually the canned tomatoes are labeled something exactly like that)
I just chop the garlic, saute it in the olive oil, once it sizzles, I add the other spices and parsley and let those saute for no more than a minute. (the spicier you like it, the more crushed red pepper you should add! Put in at least a teaspoon either way though) Then add the tomatoes and stir in. It's simple but comes out with a really good flavor.