01 - Bring a large pot of water to a boil. Add ramen noodles and cook just until al dente. Drain immediately to avoid overcooking and set aside.
02 - Heat olive oil in a saucepan over medium heat. Add minced garlic and sauté for 1 minute until fragrant. Stir in butter until melted, then add flour and cook, stirring constantly, for 1 minute to form a roux. Gradually whisk in milk, ensuring no lumps remain. Simmer until mixture thickens. Add grated Parmesan, salt, and black pepper, stirring until cheese has melted and sauce is smooth.
03 - In a large mixing bowl, combine drained ramen noodles, shredded chicken, and the garlic-Parmesan sauce. Gently fold together until well coated, then transfer mixture to a greased baking dish.
04 - In a small bowl, toss panko breadcrumbs with olive oil or melted butter until evenly coated. Sprinkle breadcrumb mixture evenly over the prepared ramen mixture in the baking dish.
05 - Bake in a preheated oven at 375°F (190°C) for 20 to 25 minutes, or until the topping is golden brown and the casserole is bubbling. Remove from oven and garnish with chopped parsley, if desired.