Potato Truffle Charlotte

Ingredients:

Basic Ingredients:
• 2 pounds peeled and quartered Yukon Gold potatoes,
• 1 pound peeled long white potatoes
• 4 tablespoons butter
• 1/2 cup cream
• 1/2 cup grated Parmigiano-Reggiano cheese, plus 1/4 cup for garnish
• 2 black truffles
• Chopped chives

For seasoning:
• Salt and pepper

Oils for cooking:
• 2 tablespoons olive oil
• Truffle [...]