Ingredients

1 tablespoon olive oil

1 medium onion, halved and sliced into 1/4-inch-thick wedges

1 red bell pepper (ribs and seeds removed), thinly sliced lengthwise

1 green bell pepper (ribs and seeds removed), thinly sliced lengthwise

Coarse salt and ground pepper

2 tablespoons red-wine vinegar

Reserved Chili-Rubbed Skirt Steak, very thinly sliced, or or 1 1/2 pounds cooked skirt steak

4 crusty Italian hero rolls (about 3 ounces each), split in half horizontally, insides torn out to form a hollow

6 ounces thinly sliced (about 10 slices) pepper Jack cheese

Preparation

Preheat broiler with rack 6 inches from heat. In a large skillet, heat oil over medium-high. Add onion and peppers; cook, stirring often, until softened and beginning to char, 10 minutes. Season with salt and pepper. Remove from heat; stir in vinegar and steak.

Place bottom halves of rolls on a large rimmed baking sheet; dividing evenly, top each with meat mixture, then cheese slices. Broil until cheese has melted, about 2 minutes. Remove from oven; transfer to a cutting board.