01 - Preheat oven to 400°F for toasting rolls and melting cheese.
02 - Heat 1 tbsp olive oil in large skillet over medium heat. Add sliced onion and bell peppers. Sauté 8-10 minutes, stirring occasionally, until softened and lightly caramelized. Remove and set aside.
03 - Add remaining 1 tbsp olive oil to same skillet. Add sliced chicken, salt, pepper, garlic powder, and paprika. Cook 6-8 minutes, stirring occasionally, until chicken is cooked through and lightly browned.
04 - Return sautéed vegetables to skillet with chicken. Stir to combine and heat through for 2 minutes.
05 - Slice hoagie rolls lengthwise, leaving one edge intact. Spread softened butter on insides. Place on baking sheet cut side up and toast in oven 3-4 minutes until golden.
06 - Divide chicken and vegetable mixture evenly among toasted rolls. Top each with 2 slices provolone cheese.
07 - Return sandwiches to oven for 3-4 minutes until cheese is melted and bubbly.
08 - Serve sandwiches immediately while hot.