A very simple sauce, a bit of chopping and then plunging tomatoes into boiling water so that I could easily peel and seed them, and I was on my way.
This sauce has just a small amount of chopped chiles in adobo sauce (found canned in the Latin area of your market.) This gives it just a little bit of umph of smoky, spice flavor. I honestly couldn't detect it much in the half chile that I put in. I would try a whole chile next time. Speaking of those canned adobos, it took me a while to realize that you could throw the extra chiles in little zips and freeze them for later use. This is super convenient when you only need one!
After simmering away on its own for a while, the mixture is ready for the food processor.