1. Drain potatoes and discard liquid. Drain pineapple and set pineapple and juice aside.
2. In a small heat-resistant non-metallic bowl melt butter in Microwave Oven 30 (40) seconds.
3. Place potatoes in a medium-sized bowl and mash with a potato masher or fork.
4. Add melted butter and brown sugar. Stir until well combined.
5. Stir in pineapple juice until desired consistency is reached. Fold in pineapple tidbits and marsh-
mallows. Butter a shallow 1 1/2-quart non-metallic casserole and spoon potato mixture into casserole.
6. Heat, uncovered, in Microwave Oven 5 to 6 (6 1/2 to 8) minutes or until potato mixture is heated through and marshmallows begin to melt.