While technically possible, roast crispy leeks aren't something that normally comes out the way that one hopes. It takes a very high, consistent temperature, which means that most standard ovens simply won't cut it. High-end broilers will roast leeks crispy, but it's vitally important to get out as much of the moisture as possible. For those who wish to give it a try, compress and dry your salted leeks between paper towels for up to a full day.