Vermont Cheddar Mashed Yukon Golds

Place potatoes in a large Dutch oven and add enough water to cover. Bring to a boil over high heat. Boil until very tender when pierced with a fork, 20 to 25 minutes. Remove from the heat. Drain and return the potatoes to the pot. Mash with a potato masher. Stir in 1 1/4 cups cheese until melted. Add buttermilk, salt and pepper and stir to combine. Gently fold in 3 tablespoons chives. Transfer to a serving dish and garnish with the remaining 1/4 cup cheese and 1 tablespoon chives.