Loteria Grill at The Grove in Los Angeles (sadly no longer there) introduced me to the various rojo salsas that could be mixed into tacos or enchiladas and I was hooked! I learned from my co-workers that it was the dried chilies plus spices and herbs that made these amazing sauces. So I set out to make it myself. What a revelation!
Not only is it easy to make your own sauce, but it tastes so much better than a can or a jar (naturally) but truly doesn't take much more time to make than the opening of said can or jar. You pour boiling water over dried chilies, spices, garlic and herbs, and let it soak for at least 30 minutes, then puree it with canned tomatoes and presto!
By the way, in case you didn't know, any blender blade and cap will fit in a regular (not wide mouth) canning jar and then you can blend your sauce straight into the jar, no need to scrap it out of the blender carafe. I have been doing this for more than a decade, never using my carafe at all. It is wonderfully handy for making salad dressing too!