Peckish

I've often thickened the red sauce by reducing it in a saucepan, then adding corn starch and cold water.
I really dislike that thin canned sauce, it's so flavorless. My co-worker is half Mexican, she told me how to make good enchilada sauce from scratch, it sounded very simple and easy, but I've forgotten some of the ingredients. I need to have her tell me again and this time I'll write it down! I think it was very similar to my arrabbiata sauce, which is roasted tomatoes, garlic, shallots, and spices, only the enchilada sauce had the addition of guajillo peppers (or a similar pepper).