1. Pat the chicken breasts dry with paper towels, then season both sides with salt, black pepper, paprika, and garlic powder.

2. Heat the olive oil in a large skillet over medium-high heat. Add the seasoned chicken in a single layer and sear for 4 to 5 minutes per side, until lightly golden. Transfer the chicken to a plate; it does not need to be fully cooked yet.

3. Reduce the heat to medium and add the butter to the same skillet. Once melted, stir in the minced garlic and cook for about 30 seconds until fragrant.

4. Sprinkle the flour over the melted butter and whisk continuously for 1 to 2 minutes to form a smooth roux.

5. Slowly pour in the chicken broth while whisking to prevent lumps, scraping up any browned bits from the bottom of the pan.

6. Whisk in the heavy cream and bring the mixture to a gentle simmer, cooking for 2 to 3 minutes until slightly thickened.

7. Lower the heat and add the mozzarella, cheddar, and Parmesan cheeses a handful at a time, stirring until each addition is fully melted and the sauce is smooth.

8. Stir in the Dijon mustard and crushed red pepper flakes, then taste and adjust seasoning with additional salt and pepper if needed.

9. Return the seared chicken and any accumulated juices to the skillet, turning the pieces to coat them in the cheese sauce.

10. Cover and simmer on low heat for 8 to 10 minutes, or until the chicken reaches an internal temperature of 165°F (74°C).

11. Just before serving, sprinkle the chicken with chopped parsley and diced red bell pepper. Add a squeeze of lime juice for brightness if desired.

12. Serve the chicken hot with plenty of cheese sauce spooned over the top and your favorite sides.