Bake at 350° until tender but firm 4 medium potatoes.
Cool, peel, and chop. Set aside.
Melt 2 tbsp butter. Stir in 1 tbsp flour. Stir until foamy.
Add slowly, 1 cup heavy cream. Cook and stir until cream mixture bubbles.
Add potatoes, mix well, spoon into baking dish.
Dot with 2 tbsp butter, salt and pepper.
Bake at 350° about 30 minutes.