Start by seasoning your boneless, skinless chicken breasts generously with salt, pepper, paprika, and a sprinkle of garlic powder. Let sit for about 10 minutes.

In a large skillet, melt 1 tablespoon of unsalted butter over medium-high heat. Add the seasoned chicken breasts, cooking for about 5-7 minutes until golden brown. Flip halfway through. Remove and set aside.

Reduce the heat to medium, add the remaining tablespoon of unsalted butter, and let it melt. Add diced onion and sauté for 3 minutes until translucent. Stir in minced garlic and cook for another minute.

Pour in the heavy cream while stirring constantly. Bring to a gentle simmer. Add Parmesan cheese and cayenne pepper if desired, stirring until smooth. Adjust seasoning with salt and pepper.

Return the chicken to the skillet, coating it in the sauce. Reduce heat to low and let simmer for about 5 minutes, ensuring chicken reaches an internal temperature of 165°F.

Remove from heat and garnish with freshly chopped parsley. Serve hot over rice, mashed potatoes, or steamed vegetables.