This mash owes its luxurious texture to the natural creaminess of Yukon gold potatoes and a touch of olive oil. At first glance 4 cloves of garlic may seem like a lot, but the garlic mellows as it steams with the potatoes so when they are mashed together you get just the right garlic infusion.
Place the potatoes and garlic in a steamer basket fitted over a large pot of boiling water. Cover and steam until the potatoes are knife-tender, 12 to 15 minutes. Warm the chicken broth in a small pot on the stove or in a glass container in the microwave.
Remove the steamer basket and drain the water from the large pot. Transfer the potatoes and garlic to the pot, add the oil, salt, pepper, and broth and mash until smooth.