Add a few of the tomatoes and some of the liquid and tomatoes from the can to a blender.
Add 1 chipotle pepper and some of the adobo sauce.
Add 1 teaspoon of salt and blend to make a liquid puree.
Add the rest of the ingredients (remaining tomatoes, onion, cilantro, 1 more chipotle pepper, and the whole can of diced tomatoes) and pulse the blender to combine.
Taste and add more salt if needed.
