For the beef and vegetables
01 -
1 1/2 lb (680 g) shaved steak or very thin sirloin
02 -
1 teaspoon kosher salt
03 -
1/2 teaspoon black pepper
04 -
2 tablespoons neutral oil, divided
05 -
1 large yellow onion, thinly sliced
06 -
1 green bell pepper, thinly sliced
07 -
1 red bell pepper, thinly sliced
08 -
8 oz (225 g) cremini mushrooms, sliced
09 -
3 cloves garlic, minced
For the sauce and cheese
10 -
1/2 cup (120 ml) low-sodium beef broth
11 -
1 tablespoon gluten-free Worcestershire sauce
12 -
1 teaspoon Dijon mustard
13 -
1 teaspoon hot sauce, optional
14 -
6 slices provolone cheese, or 1 1/2 cups shredded provolone
15 -
1 tablespoon chopped parsley, optional