Mashed Potatoes Casserole Recipe

Preheat oven to 450°F. Mash potatoes until smooth. Combine unsalted butter and whipping cream over medium heat; stir until smooth. Add salt, ground black pepper, and ground nutmeg.

Pour mixture, egg yolks, and grated Edam cheese into potatoes; mix until smooth. Season to taste with salt. Spoon into a deep baking dish; top with frozen puff pastry sheet. Crimp edges and make a slit on top. Brush with egg wash (1 egg white mixed with 1 tablespoon water). Bake for 25 minutes or until pastry is golden and has risen slightly.