Potatoes - Twice Baked

Ingredients

• 4 large russet potatoes, each about 3/4 pound each, scrubbed and dried
• 2 to 4 tablespoons unsalted butter
• 1/3 cup sour cream
• 1 scallion, finely chopped
• Freshly grated nutmeg, optional
• 1/2 cup shredded sharp cheddar
• Kosher salt and freshly ground black pepper