Prepare the Ingredients: Dry the chicken breasts with paper towels. Season with salt and black pepper. Chop the onion, mince the garlic, and roughly chop the pepperoncini peppers.

Cook Chicken: Heat olive oil in a skillet over medium-high heat. Add seasoned chicken and cook for 5 to 7 minutes until golden brown. Transfer to a plate and keep warm.

Sauté Aromatics: In the same skillet, add onion and cook until translucent (about 5 minutes). Add garlic and stir for a minute until fragrant.

Create Sauce: Pour in pepperoncini juice and add chopped pepperoncini, chicken broth, Italian seasoning, and red pepper flakes. Bring to a gentle simmer.

Simmer Sauce: Allow to simmer for about 5 minutes, stirring occasionally to thicken.

Thicken Sauce: Stir in heavy cream and simmer for another 5 minutes until desired thickness is achieved.

Combine: Return chicken to skillet, ensuring it's coated in the sauce. Heat through for 2 to 3 minutes.

Serve: Garnish with parsley and serve hot over cooked pasta or rice.