Slice chicken into 1/2-inch strips.

Mix the fajita marinade in a bowl: whisk together Olive oil, orange juice, brown sugar, garlic, chili powder, cumin, salt and pepper.

Place sliced chicken into the marinade and mix well. Cover and refrigerate 1 – 4 hours.

Slice the onions and peppers into thin slices, removing pepper seeds and membranes.

Heat a cast iron skillet over high heat.

Pour chicken along with marinade and vegetables into the hot skillet.

Cook for 3 minutes, stirring frequently. Lower to medium-high heat and continue to cook until vegetables are softened and chicken is cooked through to 165° using a digital meat thermometer. Remove from heat and set aside.

Cut about a 2 inch piece from the top of each roll in a diamond shape, leaving the ends intact to create a place for the filling.

Preheat the broiler.

Line each roll with 2-3 slices of cheese.

Fill each with fajita mixture.

Place under the broiler for 3-5 minutes or until buns are golden brown and cheese is melted.

Slice sandwiches in half and serve immediately.