carefully to mix. Fill pineapple shells (barrels) with beef and fruit mixture. Place filled fruit upright in foil lined pan. Bake in a moderate oven (350 degrees F.) for 35 minutes. Meanwhile remove stemms from mushrooms, slightly hollowing out caps. Cook caps in butter in small frying-pan about 3 minutes. Curl up each pimiento strip and place in mushroom cap. To serve, set both "Barrels" on warm plater, spoon beef mixture over rice on individual dinner plates and garnish each serving with 3 stuffed mushroom caps.