Place peppers directly over the flame of a gas burner or in a griddle in the stove, or under a preheated broiler.
2
Roast, turning often, until black all over, about 8 to 10 minutes. Set aside to cool. Slip off the skins, cut away the stems, Slit the peppers open and remove seeds, (or use pickled red peppers in oil).
3
Puree the peppers in a food processor. (You should have about 1/2 cup puree.) Force the puree through a fine strainer set over a small bowl, using a rubber spatula; discard solids.
4
Whisk in tomato paste, oil and vinegar. Season with salt and pepper.