Millionaire's Potato - Lettuce Entertain You

Ingredients

• 10 large russet potatoes, unpeeled
• ½ cup (1 stick) unsalted butter, at room temperature
• 1 cup Fontina cheese, coarsely grated plus more for finishing
• ½ cup aged Parmesan, grated
• 1 cup heavy whipping cream
• ½ cup chopped chives, plus more for garnish
• 3 Tbsp. truffle paste (optional)
• Salt and pepper, to taste
• 1 fresh black truffle, to finish (optional)
• Truffle oil, for drizzling (optional)