Cook the fettuccine pasta according to package directions until al dente. Reserve some pasta water, then drain and set aside.
In a saucepan over medium heat, melt the butter. Add minced garlic and sauté until fragrant. Pour in the cream and bring to a gentle simmer. Season with salt, pepper, chili flakes, and Italian herbs. Stir in the mascarpone cheese until smooth, then gradually add Parmesan cheese and stir until creamy. Add reserved pasta water as needed to loosen the sauce.
Flatten the chicken breasts to an even thickness and season with salt and pepper. Place flour, beaten egg, and a mixture of crushed corn flakes, Parmesan cheese, and parsley into separate shallow bowls. Coat each chicken breast in flour, dip into egg, then press into the cornflake mixture until evenly coated.
Heat olive oil in a skillet over medium-high heat. Fry the chicken breasts for 4–5 minutes per side, or until golden brown and fully cooked. Transfer to paper towels to drain excess oil.
Toss the cooked fettuccine pasta with the Alfredo sauce until fully coated. Slice the Parmesan crusted chicken and serve over the creamy pasta. Garnish with extra Parmesan cheese and fresh parsley if desired.