One of the side effects of a constantly evolving holiday dinner menu is that you will invariably end up with an ingredient that you no longer need. For us, it was leeks this time, after I forgot that one of our guests was bringing the soup. (For the record, we were going to try out a recipe for chestnut soup. Oh well, one less dish to worry about.)
Given that we live in Minnesota, and thus that it is COLD right now, I thought a good way to use up the leeks would be to make a classic potato-leek soup. It turns out, however, that such soups (vichyssoise or not) use a lot of leeks–certainly more than the two we had on hand! Hence the version below, which is sort of a cross between potato-leek and my mom’s potato-onion soup. (That soup was the original goal, but for some reason my parents didn’t include it in the family cookbook–too basic, I guess.)
As I was pulling out ingredients to start the prep, I had another idea. In his book Everything on the Table, Colman Andrews gives a recipe for “Six-Lily Risotto,” which includes onions, leeks, scallions, shallots, chives, and garlic. (He chose the name because onions and their relatives are members of the lily family.) We had everything but chives, so I briefly thought about sauteing some shallots and garlic with the onion and leeks and then chopping some scallions for a garnish. In the end, however, I decided against it–it was three more things to chop, and I wanted to get cooking. (Besides, what was I going to call it? Potatoes are related to nightshade, but “Nightshade Soup with Lilies” doesn’t have quite the right ring to it. Maybe for Halloween…)
The most labor-intensive step here is prepping the leeks, which are notoriously dirty. Cut off the root end (half an inch or so) and the dark green tops, then cut the leeks in half lengthwise and discard the outermost layer. Rinse the leeks carefully under cold water; you will probably have to pull them apart. Once they’re cleaned and drained, start chopping…
Potato Soup with Leeks and Onion
- 4 large russet potatoes about 2 pounds, pelled and sliced 1/4-inch thick
- 3 tablespoons unsalted butter
- 2 leeks cleaned (see note below) and sliced thinly
- 1 large yellow onion peeled, quartered through root end, and sliced thinly
- 2 ribs celery sliced thinly
- freshly ground black pepper
- 3 cups whole milk
Add potatoes to a large pot of cold salted water. Cover and bring to a boil over high heat. Reduce heat to medium-low and cook for 7-8 minutes, until potatoes are fork-tender.
Once potatoes are on the heat, melt butter in a large, heavy-bottomed pot over medium-high heat.
Add onions, leeks, and celery and salt well. Cook for 15 minutes, stirring frequently. (The vegetables will give off enough water that they will soften but not actually turn golden or brown.)
Warm milk in a medium saucepan over medium-low heat.
When potatoes are tender, add them to leek-onion mixture with a slotted spoon. (Don't just drain the potatoes--you'll need some of the water.)
Reduce heat to medium-low and stir well to coat potatoes. Coarsely mash potatoes with potato masher.
Season well with salt and pepper.
Stir in about 2 ladlefuls of the water used to cook the potatoes.
Once the water is incorporated, stir in warm milk, one ladleful at a time, until the desired consistency is reached.
Season to taste with salt and pepper.
Recipe NotesCleaning leeks: Cut off the root end (half an inch or so) and the dark green tops, then cut the leeks in half lengthwise and discard the outermost layer. Rinse the leeks carefully under cold water; you will probably have to pull it apart. Once they're cleaned and drained, start chopping.