In a large skillet, heat the olive oil over medium-high heat. Add the chicken pieces, season with salt, black pepper, garlic powder, and onion powder. Cook for about 5-7 minutes, or until the chicken is browned and cooked through. Remove the chicken from the skillet and set aside.
In the same skillet, add the chicken broth and bring to a simmer, scraping up any browned bits from the bottom of the pan.
Stir in the sliced pepperoncini peppers and heavy cream, mixing well. Allow the sauce to simmer for about 3-5 minutes until it thickens slightly.
Return the cooked chicken to the skillet and stir to coat in the creamy sauce. Sprinkle the mozzarella cheese on top and cover the skillet. Cook for an additional 2-3 minutes, or until the cheese is melted and bubbly.
Remove from heat and garnish with fresh parsley before serving.