Add the chiles, soaked chile liquid, onion, garlic, canned diced tomatoes, vinegar, cumin, oregano, coriander, salt, and pepper to a blender. (Don't skimp on the salt; it really makes all the difference if this dish is undersalted).
1 14.5 oz can diced tomatoes (fire-roasted), 2 Tbsp. apple cider vinegar, 1 tsp. ground cumin, 1 tsp. dried oregano, 2 tsp. kosher salt, 1/2 tsp freshly ground black pepper, 1 tsp ground coriander