Boil potatoes until done. Drain and place in large bowl. Mash the potatoes. Add the sour cream, cream cheese, 4 T. butter, dried minced onion, salt and pepper and beat until smooth and creamy. Spread potato mixture in a greased large baking dish. Drizzle 2 T. melted butter over the top and sprinkle with paprika. Cover and bake at 350 degrees for 45 minutes; uncover and bake additional 20 minutes.
May be made ahead and refridgerated. If made ahead and refridgerated, let stand at room tempperature for 25-30 minutes before baking.