Step 1

Bring a large pot of water to a boil. Add the potatoes, garlic, and salt and simmer, partially covered, over medium heat for 15 to 20 minutes, or until the potatoes and garlic are fork-tender.

Step 2

Drain the potatoes and garlic and return to the pot over high heat. Cook, tossing the potatoes, for 1 to 2 minutes, or until all the moisture is evaporated. Transfer to a large bowl and mash with a potato masher.

Step 3

In a medium saucepan, heat the butter, oil, and milk over medium heat until the butter has melted. Add to the potatoes and whip with a wooden spoon or whisk to a smooth but not soupy consistency. Mash any pieces of garlic until totally pureed. When the liquid is absorbed, season with salt and pepper to taste. Transfer to a serving bowl and serve immediately.

Step 4

To prepare in advance, make up to 4 hours ahead, cover, and keep at room temperature. Reheat gently in the top of a double boiler over medium heat, adding extra milk as needed and adjusting the seasonings.

Step 5

The Clever Cook Could:

Step 6

Peel the potatoes and purée with a potato ricer for a very smooth consistency

Step 7

Add 1 cup freshly grated Parmesan cheese or 1 or 2 tablespoons prepared horseradish or a squirt of wasabi paste

Step 8

Add 3 finely chopped leeks sautéed in olive oil to the mashed potatoes just before serving