On 23 April 1913, King George V and Queen Mary paid a visit to the town of Leek. What better way to commemorate this royal sojourn than with a souvenir cup? And now, 100 years later, what better way to celebrate this commemorative beaker than with a dish of leeks?
As my Dear Editor can attest, I have a great fondness for leeks. [Editor’s note: It’s true. He likes leeks.] One of my favorite leek recipes, Leeks Vinaigrette Mimosa, comes from The Complete Robuchon  by Joël Robuchon and translated by Robin H.R. Bellinger. Mimosa refers to the dish’s hard-boiled egg garnish. Robuchon’s recipe serves 4.
8 medium leeks, white parts only
1 hard-boiled egg, shell removed
1 tablespoon sherry vinegar
1 teaspoon mustard
3 tablespoons neutral oil, such as grapeseed
1 shallot, peeled and minced
1 tablespoon each minced parsley, chervil, and chives
1. Carefully wash the leek whites in warm water. Tie them into little bundles so the leaves don’t separate as they cook.
2. Bring 1½ quarts (1.5 liters) water and 1 tablespoon coarse salt to a boil and add the leeks. Cook 15-20 minutes, according to their size. (You can test to see whether they are cooked by pricking one in the middle with the tip of a knife. When it is cooked, the flesh of the leek should not resist the knife at all.) Set a rack over a plate. Remove the leeks with a skimmer and set them on the rack.
3. Separate the yolk and the white of the hard-boiled egg. Crumble the yolk with a fork. Crumble the white, either by mincing it or by pressing it through a strainer with not-too-fine a screen.
4. Using a fork, beat the vinegar with 2 pinches of salt. Add a pinch of pepper and the mustard and mix. Beat in the oil.
5. Arrange the still-warm leeks side by side on a plate and dress them with the vinaigrette. Shower them evenly with the crumbled egg, shallot, and herbs.
This classic, simple dish comes together quickly and is easy to make. The sweet, soft leeks and sharp mustard vinaigrette beautifully play off of each other. Serve Leeks Vinaigrette Mimosa with a roast chicken (here) together with potatoes and you have a great meal for family, friends or visiting royalty.