Prepare the Ingredients: Slice the red bell pepper and yellow onion into thin strips. Cut the pepperoncini peppers into rings and grate the Parmesan cheese until you have about 1 ounce.

Cut and Season the Chicken: Slice the boneless, skinless chicken breasts into approximately 1/2-inch thick pieces. Season with kosher salt and freshly ground black pepper.

Brown the Chicken: Heat 2 tablespoons of olive oil over medium-high heat, add half of the seasoned chicken pieces, and cook for about 6 minutes until golden brown. Remove and repeat with the remaining pieces.

Sauté the Vegetables: Add the remaining tablespoon of olive oil, sliced red bell pepper, onion, kosher salt, and Italian seasoning to the skillet. Sauté for about 2 minutes until onions are translucent.

Create the Flavor-Infused Broth: Pour in the low-sodium chicken broth and allow it to simmer, scraping up any browned bits and reducing by half for about 2 minutes.

Whisk in the Creamy Elements: Stir in grated Parmesan cheese and heavy cream, allowing to simmer for about 3 minutes until slightly thickened.

Combine and Serve: Return the cooked chicken and add sliced pepperoncini. Toss gently to coat the chicken in the creamy sauce and let it simmer for another minute before serving.