Step 2
Prepare the leeks. Rise off any visible dirt and slice the roots from the end. Remove the dark green tops, leaving a couple inches of light green with the white portion of the leeks. (The dark trimmings can be reserved for another use, adding them to a vegetable or chicken stock, for example.) Halve the leeks lengthwise, then cut crosswise in 1/2-inch slices. Dump the slices in a colander or salad spinner and rinse thoroughly; if you don’t, you risk having a gritty, sandy quiche, as leeks often hide dirt deep in their layers. Let the leeks drain well, or spin dry.