Cheesesteak Empanadas

Name: Cheesesteak Empanadas
Ingredients: 2 tablespoons vegetable oil; 8 ounces sirloin steak, sliced into very thin strips about 1 inch long; Kosher salt and freshly ground black pepper; 2 cloves garlic, minced; 1/2 small yellow onion, thinly sliced; 1/2 small green bell pepper, thinly sliced; 4 ounces provolone, cut into small cubes; 1 large egg; One 17.3-ounce package frozen puff pastry, thawed (2 sheets); All-purpose flour, for dusting; 1 cup prepared jarred cheese sauce, such as Cheez Whiz; 2 tablespoons sliced pepperoncini, diced with juice