1. Cut hens in half, rinse and pat dry. Season lightly with salt and pepper. Saute cornish halves in butter or margarine until browned, about 10 minutes. Remove from pan.
2. In same pan, saute mushrooms and onion until soft. Stir in apple juice or cider and brandy.
3. Return cornish halves to pan, reduce heat, cover and simmer for 25 minutes. Remove cornish and keep warm.
4. Blend cornstarch with small amount of water. Stir sour cream and cornstarch mixture into pan liquid. Heat sauce until thickened and pour over cornish.