Salsa Taquera (Philadelphia)

Sweetness from the tomato and tang from the tomatillos complement the mellow (but not overpowering) onion and garlic flavours in this salsa from the Philadelphia taco institution South Philly Barbacoa. Soaking the jalapeños and chiles de árbol tempers their piquancy without dulling their flavours.

2½ cups water, divided
2 Tbsp. + 1 tsp. sea salt, divided
2 medium-size jalapeños, seeded and ribs removed (~ 2½ oz)
3 small dried chiles de árbol, seeded (~ 1/8 oz)
2 large tomatoes (~ 1 lb)
3 fresh tomatillos, husks removed (~ 12 oz)
½ cup white onion, thinly sliced (from 1 small onion)
1 large clove garlic, thinly sliced (~ 1 tsp.)
3 sprigs cilantro (~ ¼ oz)
½ tsp. ground cumin
½ tsp. dried oregano
¼ cup extra-virgin olive oil
1 tsp. white wine vinegar
¼ tsp. black pepper, freshly ground

Combine 2 cups water and 2 Tbsp. salt in a small saucepan; bring to a boil over medium-high. Stir until salt is fully dissolved. Remove from heat. Let cool about 15 minutes. Add jalapeños and chiles de árbol; soak for 1 hour.

Meanwhile, heat a comal or cast-iron skillet over medium-high. Add tomatoes and tomatillos; cook, turning occasionally, until charred in spots and starting to soften, about 15 minutes. Remove from the heat and set aside until ready to use.

Drain chile mixture and transfer to a large pot. Add charred tomatoes and tomatillos, onion, garlic, cilantro, cumin, oregano and remaining ½ cup water. Bring to a boil over medium-high heat; boil, stirring occasionally and breaking down tomatoes using the back of a wooden spoon, until tomatoes and tomatillos are soft and falling apart, about 5 minutes. Remove from the heat.

Transfer mixture to a blender. Secure lid on blender, and remove center piece to allow steam to escape. Place a clean towel over opening. Process until smooth, about 30 seconds.

Wipe large pot clean. Add oil to pot; heat over medium-high. Carefully add puréed tomato mixture. (Sauce will splatter.) Using a long-handled wooden spoon, stir in vinegar, black pepper and remaining 1 tsp. salt. Bring to a boil and boil, stirring often, until salsa thickens slightly and you can see bottom of pot when stirring, about 8-10 minutes.

Remove from heat. Season with additional salt and vinegar to taste. Serve hot or at room temperature.