Gently cooking thinly sliced leeks and lemons in olive oil for just under an hour creates a bright, springy condiment that can be added to pasta, rice, grilled steak, roasted cauliflower, and more. The oil alone can add character to vinaigrettes and pots of cooked grains, and you can even use it to confit other vegetables or alliums. Use an instant-read thermometer, if you have one, to keep the oil from getting too hot or too cold—but if you don’t, just watch the oil, and taste a leek here and there to make sure you get to a relaxed, just beyond al dente texture.
- Cut the leeks into ¼-inch bias discs. Rinse, and rinse again, in a large bowl to dislodge any sand. Drain and dry well in a salad spinner or with a towel. Dry out the large bowl and add the leeks back to it. Slice lemons into ¼-inch discs and then into quarter pie wedges, discarding any seeds. Add to the leek bowl with fennel seeds, chile pods, and salt. Toss well and let sit for 5 minutes.
- Add the leek and lemon mixture to a 2-quart high-sided pot with enough olive oil to almost cover it, about 2¼ cups. The pot should look full, like there’s not enough oil to cover the vegetables, but there is. If you use a pot any larger or a pan any wider, you will need more olive oil. With the back of a spoon, gently press down on the leek and lemon pieces so they become submerged.
- Turn the heat on to low and, with a thermometer, make sure the confit oil stays in the range of 140–160ºF—no less, no more. Every 5 minutes, gingerly stir (without breaking the leek rings or lemon pieces) to mix the hotter oil in with the cooler oil closer to the surface and ensure that the leek and lemon pieces cook evenly. Taste a leek ring here or a lemon piece there to gauge doneness, which means the leeks should be tender, not squeaky, and the lemon piths should be fully saturated with oil, relaxed, in between firm and mushy—about 40 minutes.
- Serve immediately while warm or let cool before storing in your refrigerator. The confit will keep for about 2 weeks refrigerated and stored in its oil.
Christian is a California based chef, writer, and freelance recipe developer. He spent the last five years cooking as sous chef at Zuni Café. He has a bi-monthly cooking column in the San Francisco Chronicle and has words in Edible Magazine, Food52, and Epicurious. When he's not at home he's traveling to Mexico, exploring its cuisine and his heritage.