01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Heat olive oil in a large skillet over medium heat. Add minced garlic and sauté until fragrant, approximately 1 minute.
03 - Pour heavy cream and milk into the skillet. Bring to a gentle simmer while stirring constantly.
04 - Add Parmesan cheese, salt, black pepper, red pepper flakes, and Italian seasoning. Stir continuously until cheese completely melts and sauce achieves smooth consistency.
05 - Add cooked chicken to the Alfredo sauce. Toss until thoroughly coated, then remove from heat.
06 - Slice bread lengthwise. In a small bowl, combine softened butter, minced garlic, and chopped parsley. Mix until evenly incorporated.
07 - Spread garlic butter mixture evenly over cut surfaces of both bread halves. Spoon chicken Alfredo filling on top, distributing uniformly.
08 - Sprinkle shredded mozzarella and provolone cheese over the chicken mixture, covering completely.
09 - Transfer assembled bread to prepared baking sheet. Bake for 12 to 15 minutes until cheese melts completely and bread edges turn golden brown.
10 - Remove from oven and allow to cool for 3 to 5 minutes. Cut into individual pieces and serve while warm.