Start by seasoning your boneless skinless chicken breasts or thighs with salt and pepper. Heat a large skillet over medium-high heat and add a splash of olive oil. Once shimmering, place the chicken in the skillet and cook for about 6-7 minutes per side until golden brown and cooked through, reaching an internal temperature of 165°F. Then, transfer the chicken to a plate and cover it to keep warm.

In the same skillet, lower the heat slightly and add chopped onions. Sauté for about 3-4 minutes until they turn translucent, stirring often to prevent burning. Next, add minced garlic and sauté for an additional 1-2 minutes until fragrant, making sure it doesn't brown.

Stir in the sliced pepperoncini peppers along with the dried oregano and basil. Pour in the chicken broth and half-and-half, stirring to combine all the ingredients. Increase the heat to bring the mixture to a gentle simmer, allowing the flavors to meld together for about 5 minutes.

Return the cooked chicken to the skillet, ensuring it’s well coated in the sauce. Let it simmer together for another 2-3 minutes, stirring occasionally. To elevate the creaminess, gradually sprinkle in the grated Parmesan cheese, stirring until melted and fully incorporated.

Once everything is well combined and heated through, remove from heat and serve your Pepperoncini Chicken Skillet hot over a bed of rice or mashed potatoes.