What part of the leek should you use? Some people only like to use the white and light green part of the leek, as the dark green upper sections are significantly tougher. However, they're still perfectly edible, and the leeks cook for long enough in this recipe that you can absolutely use them! We remove about inches off the very top and trim any damaged leaves. Just make sure to sauté until the darkest green sections are tender. 

Washing leeks: Chop the leeks first and then soak them in water or use a salad spinner to get rid off all the excess dirt that resides in between its layers.

Mashing potatoes: For the fluffiest mashed potatoes, use a ricer or a food mill instead of a potato masher. It's easier, and you'll have a much smoother and more even texture.

Deglaze frequently: To prevent your leeks from burning and sticking to the bottom of your pan, add a splash of vegetable broth every couple of minutes.

To get your cheese and butter to melt into your mash, either mash the potatoes while they're still warm, or heat the mash over medium low heat and add everything in.

Storage: Store leftovers in an airtight container in the refrigerator for up 5 days. Microwave or reheat on the stovetop. If they start to dry out, you can always mix in a little more warm milk.