To make salsa: If using fresh tomatoes, place in a pot of simmering water and let cook until soft, about 15 minutes. Drain, remove stem ends, and purée with a blender.
In a skillet, heat oil until shimmering. Add chilies, onion, garlic, cloves and canela (or spices), sprinkle with salt and cook over medium-low heat, stirring, until softened and golden, about 8 minutes. Add tomato purée or canned tomatoes and simmer, stirring often, until thickened and slightly sweet, about 15 minutes. Taste for salt. Purée with a blender until smooth.
