Mashed Cauliflower & Yukon Golds

Place potatoes and cauliflower in a medium saucepan and cover with cold water. Bring to a boil over high heat. Reduce heat to medium and simmer until tender, about 18 minutes. Drain and return the vegetables to the pan. Cook over medium-high heat, stirring often, until dry, about 3 minutes.

Mash the vegetables with a potato masher. Add sour cream and butter and mash until mostly smooth. Stir in salt and pepper. Transfer to a large serving bowl and sprinkle with chives.