-
Heat oven to broil.
-
Place tomatoes and chiles on a sheet pan and broil each side until they are blackened. About 5 minutes per side, give or take (my serranos were black sooner, so I pulled them early.)
-
Remove from oven and let cool.
-
In the meantime, turn your oven to bake at 450 degrees.
-
Slice the onions and peel the garlic.
-
Place on a different sheet pan and let roast until they are soft and brown, about 15 minutes. Let cool.
-
Chop cilantro and set aside.
-
Over the first pan, peel the skin off the tomatoes and cut out the core, letting the pan catch the tomato juice.
-
Peel the skin from the chiles.
-
Depending on your preference of chunky or not so chunky, place the tomatoes in a blender (not-so) or a food processor.
-
Pulse the tomatoes (with the extra juice from the pan), add the onions, chiles, and garlic, pulse until desired consistency.
-
Pour into bowl, stir in cilantro, salt, and vinegar.
-
To freeze: fill quart size Ziploc freezer bags with desired amount. Freeze up to 5 months. To thaw, let sit out at room temperature for about 30 minutes.