Preheat your oven to broil.

Bring two quarts of water to a boil.

Add the tomatoes, and boil 3-5 minutes, or until the skins begin to loosen.

Remove the tomatoes from the water, slice off the tops, and slide off the skins with your fingers, discarding them.

Place the peppers under the broiler for 2-3 until they start to shrivel and blacken.

Using silicone-tipped tongs, flip the peppers and broil another 2-3 minutes.

Puree the tomatoes in a high-quality blender or food processor until smooth. My NutriBullet Blender had these tomatoes perfectly pureed in under ten seconds.

Add the pepper(s), onion, cilantro and salt, and blend until smooth again.

Gradually add more salt in 1/4 teaspoon increments until it suits your taste.