2 pounds tomatoes
2 serrano chilies, chopped (discard seeds if you want a milder sauce)
3 tablespoons canola oil
1 small onion, chopped
1 tablespoon minced garlic
Salt to taste

Preheat oven to 400 degrees F. Roast tomatoes on a baking sheet for 30-45 minutes, depending on the size of the tomatoes, until the tomato skins are wrinkled and slightly charred. The flesh will be soft. Transfer to the bowl of a food processor (if you don't have one, just use a large casserole and a potato masher). Process/mash until smooth, then add the serrano chilies and continue to process. Set aside.

In a skillet, heat the oil over medium heat. Add onion and garlic and cook, about 5 minutes, or until just beginning to turn color. Add tomato-pepper puree and cook, stirring frequently, until a bit thickened, about 10 minutes. Add salt to taste and cook a few minutes more. Your sauce is ready to be used in any recipe, or can be refrigerated for 3 days, or frozen for 2 months.

It is lovely in huevos rancheros (coming up), and also on grilled fish, veggies, or pasta. We love it on roasted potatoes, or as a dip for tortilla or potato chips.