Saute onions and mushrooms in frying pan with Brown's orange juice and 1/2 cup butter. Gradually increase temperature as onions and mushrooms cook until heat is very high. All moisture should cook into onions and mushrooms. At same time, saute chicken in 1/2 cup butter in separate pan. When chicken is cooked completely, add onion/mushroom mixture and pour Brown's heavy cream over the top. Stir and heat thoroughly. Great served over rice.