In a covered Dutch oven cook sweet potatoes in enough boiling salted water to cover for 25 to 30 minutes or until tender; drain. Return to pan.
Meanwhile, preheat oven to 350 degrees F. Grease a 3-quart casserole; set aside. Slightly mash potatoeswith a potato masher. Stir in eggs, brown sugar, butter, milk, and lemon juice. Transfer mixture to the prepared casserole. Top with pineapple and cheese.
Bake, uncovered, for 30 to 35 minutes or until heated through.