8 medium russet potatoes (4 pounds)
1 head garlic cloves (about 15) , peeled
1 1/2 cups milk
1/2 cup (1 stick) butter
Peel potatoes. Quarter lengthwise, cut crosswise 1/2 inch thick. In a 5-quart saucepan, combine potatoes and garlic, cover with water by 1 inch. Add 1 tablespoon salt. Bring to a boil, reduce heat and simmer until potatoes are easily pierced with the tip of a paring knife, 30 mins.
Drain; return garlic and potatoes to pan. Stir over medium-high heat until dry, 1-2 mins. Remove from heat.
In a small saucepan, bring milk to a boil, pour over potatoes. Add butter, cut into small pieces and 1 teaspoon salt. Mash until smooth and creamy.
Source: Martha Stewart Everyday Foods