5 tablespoons dark brown sugar, divided |
3/4 teaspoon black pepper |
2 (1-pound) flank steaks |
1 cup chopped onion |
1 cup tomato paste |
3 tablespoons worcestershire sauce |
3 tablespoons molasses |
3 tablespoons cider vinegar |
1 tablespoon chili powder |
1 teaspoon garlic powder |
1 teaspoon dry mustard |
1 teaspoon ground cumin |
1/2 teaspoon salt |
10 (2 1/2-ounce) submarine rolls, halved |
red onion slices (optional) |
dill pickle slices (optional) |