Preheat oven to 400°F.
Add cubed chicken to a medium bowl; top with olive oil, honey, soy sauce, garlic, and pepper, and mix until coated. Cover with plastic wrap and refrigerate for at least 30 minutes.
Prepare the vegetables by cutting into 1-inch squares.
Arrange the red onion, bell peppers, and marinated chicken onto a baking sheet and brush with remaining marinade.
Bake for 20–30 minutes or until chicken is no longer pink.
Top Martin’s Hoagie Rolls with chicken and veggies; sprinkle with parsley and serve.