Makes 10 cups
This basic recipe, made sour with vinegar and sweet with honey, is quite malleable—so add your favorite ingredients to flavor it: Chile flakes add heat, crushed toasted nuts add texture and depth, chopped fresh herbs brighten it.
This makes far more than you will need for any one recipe, but you can freeze what you don’t use in 1-cup portions in rigid freezer-safe containers with tight-fitting lids or in resealable plastic bags. Thaw at room temperature or defrost in the microwave before using.
¼ cup canola oil
4 yellow bell peppers, cut lengthwise into ¼-inch-thick strips
4 red bell peppers, cut lengthwise into ¼-inch-thick strips
3 large yellow onions, cut into slivers
15 cloves garlic, roughly chopped
6 tablespoons tomato paste
1 cup white wine vinegar
½ cup dry white wine
2 cups Tomato Sauce (here)
2 tablespoons honey
2 tablespoons kosher salt
½ teaspoon fresh ground black pepper
In a large heavy-bottomed pot over medium-high heat, combine the canola oil and peppers and sauté until just softened and fragrant and the peppers begin to release a little liquid, 5 to 8 minutes. Add the onions and garlic and sauté just until the onions are soft; do not let them take on any color. Add the tomato paste and stir to combine. Add the vinegar and white wine and cook until the liquid is reduced by half. (The larger the pan, the faster the liquid in the mixture will reduce.)
Add 6 cups water, the tomato sauce, honey, salt, and pepper and stir. Bring the mixture to a boil, then reduce the heat and simmer until the liquid thickens to the consistency of a salsa. The peppers and onions will keep, tightly covered, in the refrigerator for 1 week, or for up to 3 months in the freezer.