Slice each boneless, skinless chicken breast into 2-3 thinner slices, about ½ inch thick. Use a meat tenderizer to pound the slices to an even thickness if needed. Season each side of the chicken slices with Italian seasoning, salt, and pepper.

Brush one side of each piece with melted butter. Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Once the oil is hot, add the chicken slices to the skillet, buttered side down.

Sauté for about 4-5 minutes per side, or until a golden-brown crust has formed. Transfer the seared chicken to a plate and set aside. Repeat with remaining chicken slices, adding more oil if needed.

In the same skillet, remove any excess oil, leaving behind about 1 tablespoon. Reduce heat to medium and add the cream of chicken soup, milk, sour cream, onion powder, and Ranch seasoning mix.

Whisk until everything is well combined and smooth. Let the sauce come to a gentle bubble, then reduce heat to low. Cook for about 5 minutes, stirring occasionally, until the sauce thickens slightly.

Return the seared chicken slices to the skillet, nestling them into the creamy sauce. Spoon some sauce over each piece to ensure they’re fully coated. Partially cover with a lid and let the chicken simmer in the sauce for about 10 minutes.

Remove the skillet from the heat and let it rest for a few minutes before serving. Spoon the creamy ranch sauce over the chicken and serve with mashed potatoes, baked potatoes, or steamed vegetables.