Peel potatoes and cut in half. Place in a large pot and cover with 2 inches of water. Bring to a boil and add 1 Tbs. kosher salt. Cook until tender, 20-30 minutes.
Drain the potatoes and return them to the pot. Place pot back on stovetop for 5 minutes to dry out potatoes.
Transfer the potatoes to a mixing bowl with the paddle attachment. Add salt and mix on low speed just until potatoes are broken up and mashed. Add sour cream and increase speed to medium. Add butter and increase speed, mixing only until potatoes are smooth and creamy. Mix in chives and transfer to a serving dish.