Preparation Bring large pot of salted water to boil. Add potatoes and garlic; reduce heat to medium and simmer with lid slightly ajar until tender, 20 to 25 minutes. Drain potatoes; return to pot. Toss potatoes and garlic over high heat until moisture evaporates, about 2 minutes. Heat milk with butter in small saucepan over medium heat until butter is melted; set aside. Using potato ricer, press potatoes and garlic into large bowl. Add milk mixture; stir to blend. Season to taste with salt and pepper. DO AHEAD: Can be made 2 hours ahead. Transfer to microwave-safe bowl; let stand at room temperature. Reheat in microwave in 1-minute intervals until heated through, stirring occasionally, about 4 minutes.
Preparation Bring large pot of salted water to boil. Add potatoes and garlic; reduce heat to medium and simmer with lid slightly ajar until tender, 20 to 25 minutes. Drain potatoes; return to pot. Toss potatoes and garlic over high heat until moisture evaporates, about 2 minutes. Heat milk with butter in small saucepan over medium heat until butter is melted; set aside. Using potato ricer, press potatoes and garlic into large bowl. Add milk mixture; stir to blend. Season to taste with salt and pepper. DO AHEAD: Can be made 2 hours ahead. Transfer to microwave-safe bowl; let stand at room temperature. Reheat in microwave in 1-minute intervals until heated through, stirring occasionally, about 4 minutes.