3poundspotatoesYukon Gold or Russet, peeled and cut into 3-4 inch cubes
⅓cupsalted butter(78 grams) Plus additional butter for serving, if desired.
1 mediumleek, whites onlyCleaned, quartered lengthwise, and sliced thinly
¾ cuphalf and half or whole milkwarmed
⅓cupshredded Gruyere cheese(1.5 ounces/33 grams)
½teaspoonkosher saltor to taste
¼teaspoon black pepperor to taste
Prevent your screen from going dark
Place potatoes in a large stockpot or Dutch oven and cover with water. Bring the water to a boil on high heat, then reduce the heat to low and cover with a lid. Simmer for 20-30 minutes, until the potatoes are tender, then drain.
While the potatoes are simmering, melt butter in a skillet over medium heat. Add the sliced leeks and cook until they are soft, 3-5 minutes. Add the minced garlic and saute for an additional 60 seconds.
Add the drained potatoes back into the stockpot or Dutch oven and mash using a potato masher or ricer.
Add in the cooked leeks and garlic, being sure to get all of the butter added to the potatoes. (You can reserve a tablespoon of leeks to garnish the potatoes if you'd like.) Then add the sour cream, warm milk, shredded gruyere, salt, and pepper. Stir until combined.
You can add more milk to reach desired texture. Top with reserved leeks and additional slices of butter, if desired. Serve immediately.