Season and sear the chicken:
Pat the chicken breasts dry with paper towels, then season both sides with salt, pepper, and paprika. In a large skillet over medium heat, add olive oil or butter and sear the chicken for 4-5 minutes on each side, until golden brown. Remove the chicken from the skillet and set aside.

Prepare the garlic Parmesan sauce:
In the same skillet, melt the butter over medium heat. Add the minced garlic and sauté for 1-2 minutes until fragrant, being careful not to let it burn. Sprinkle the flour over the garlic and stir constantly for about 1 minute to create a roux.

Add the liquids and cheese:
Gradually whisk in the chicken broth, followed by the heavy cream, ensuring there are no lumps. Let the mixture simmer gently for 3-4 minutes until it thickens slightly. Stir in the Parmesan cheese, Italian seasoning, and red pepper flakes (if using). Adjust the seasoning with salt and pepper to taste.

Combine and simmer:
Return the seared chicken breasts to the skillet, spooning the sauce over them to coat. Lower the heat to a gentle simmer, cover, and cook for 8-10 minutes, or until the chicken is cooked through (internal temperature should reach 165°F/75°C).

Garnish and serve:
Sprinkle with freshly chopped parsley and a little extra Parmesan cheese. Serve immediately over pasta, rice, or with crusty bread to soak up the creamy sauce.