Clean and dry hens. Season inside and out with salt and pepper and refrigerate overnight. When ready to bake, insert a whole onion in the cavity of each hen and place in an open roasting pan, leaving space between them.
In a saucepan, place butter, Kitchen Bouquet and orange marmalade. Heat until butter is melted and mixture is blended. Spoon this over the hens and bake at 350 degrees until hens are tender, about 1 1/2 hours, basting often. If sauce cooks down before hens are done, add a little hot water to the pan to assure having sauce left to accompany the hens. If hens appear to be getting dry during baking, place foil loosely over pan to retard browning.