Preheat oven to 425°F. Season hens and hen cavities with salt and pepper.
In small bowl, blend I Can't Believe It's Not Butter!® Spread, shallot and tarragon; evenly spread under skin. Place 1 lemon wedge in each hen.
In 18×12-inch roasting pan, on rack, arrange hens breast side up; tie legs together with string. Roast uncovered 15 minutes.
Meanwhile, prepare Double Mushroom Stuffing.
Decrease heat to 350°F and place Double Mushroom Stuffing casserole in oven with hens. Continue roasting hens 30 minutes or until meat thermometer inserted in thickest part of thigh reaches 180°F and stuffing is golden. Remove hens to serving platter and keep warm. Remove rack from pan.
Skim fat from pan drippings. Blend flour with reserved broth from stuffing; stir into pan drippings. Place roasting pan over heat and bring to a boil over high heat, stirring frequently. Reduce heat to low and simmer, stirring occasionally, 1 minute or until gravy is thickened. Serve gravy and stuffing with hens.