Start by pounding the chicken breasts to an even 1-inch thickness using a meat mallet. Season both sides generously with salt and pepper.
In a large skillet over medium-high heat, melt 1 tablespoon of butter along with 1 tablespoon of olive oil. Sear the chicken breasts on each side until golden brown, approximately 4-5 minutes per side. Remove from skillet and set aside.
Lower the heat on your skillet to low, add the remaining butter until melted, then sprinkle in 1 tablespoon of flour, stirring constantly for about one minute to create a roux.
Gradually pour in 1 cup of low sodium chicken broth while scraping up any browned bits from the pan. Next, incorporate half a cup of milk, one-fourth cup sour cream, onion powder, garlic powder, Italian seasoning, and the Ranch seasoning mix.
Return the seared chicken along with any juices back into the skillet, ensuring they are well-coated with the sauce. Allow everything to simmer gently until heated through.
Plate your creamy ranch chicken right away while it’s still hot! Garnish with fresh parsley if desired.