Created by lazyme on September 18, 2020
Step 1: Preheat oven to 400ºF.
Step 2: Cut top 1/4-inch garlic head and wrap head in foil.
Step 3: Roast garlic 40 to 50 minutes, or until very soft, and cool.
Step 4: Squeeze roasted garlic from head and reserve.
Step 5: In a 4-quart saucepan cover potatoes with water by 2-inches and simmer until very tender, about 30 minutes.
Step 6: Drain potatoes in a colander (do not peel).
Step 7: Transfer potatoes while still hot to a large bowl and add butter.
Step 8: With an electric mixer on low speed mash slightly.
Step 9: Beat in sour cream, buttermilk, chives, and oil until combined well.
Step 10: Add Parmesan, reserved garlic, pepper, and salt to taste, beating until smooth.