Pound chicken breasts slightly to uniform thickness. Preheat non-stick skillet over medium heat for 3 minutes, then melt 4 tablespoons butter. Sauté the chicken breasts, 2 at a time in the melted butter until browned on both sides. Place browned chicken in a medium-sized sauce pan.
Add remaining two tablespoons of butter to skillet, and then sauté the onion until soft and brown, about 4 minutes Add onions to chicken in sauce pan.
Add 5 tablespoons flour to skillet, and sauté about 2 minutes, until slightly browned. Add stock and whisk until smooth. Add salt, pepper and garlic powder, and then pour over chicken in sauce pan. Add ranch dressing and stir.
Bring mixture to boil in sauce pan, then cover and simmer over medium low for 30 minutes.
I serve with homemade biscuits to mop the gravy, along with mashed potatoes, or wild rice.