Sauce for Chiles Rellenos

• half of 1 medium onion, sliced
• 3 tablespoons vegetable oil
• 1 (28 oz) can Italian style tomatoes
• 1 teaspoon garlic, pressed or smashed and finely minced
• salt and pepper
• 1/2 teaspoon dried leaf oregano, crushed
• 1 teaspoon sugar
• chicken broth or tomato juice, to use if sauce is too thick

Sauté onion slices in hot oil in medium-sized saucepan.
Process canned tomatoes in blender or food processor with garlic; strain. Add tomatoes and garlic to sautéed onion slices. Season with salt and pepper and add oregano. Add sugar and correct seasoning. Cover and cook over medium heat for 5 minutes. If sauce thickens too much, add chicken broth or tomato juice and cook 2 minutes longer. Take to the table in a sauceboat or serve over Chiles Rellenos to cover.
Adapted from "Mexican Family Cooking"