Waldorf salad with candied walnuts and celery root

Combine sugar and water in a small saucepan for a simple syrup, with a pinch of salt and pepper.

Bring to a boil, make sure the sugar dissolves, and boil about one minute.

Add the walnuts and let them steep in the syrup about 20 minutes.

Preheat the oven to 250 degrees Fahrenheit.

Cut the celery root into quarter-inch cubes: slices, then large sticks, then cubes; trim the yellowed outside.

Cover with water, bring to a boil and simmer about 10 minutes, until cooked but not mushy.

Toss the walnuts in the syrup, drain, and spread on a sheet so they do not touch.

Bake the walnuts 30 to 35 minutes, then let them cool completely, about an hour.

Put the egg yolk in a large bowl, add the mayonnaise and yogurt and whisk; add the Dijon mustard and lemon juice.

Add the sherry vinegar, then the oil slowly; season with about a third of a teaspoon of salt and freshly ground pepper. Refrigerate.

Drain the celery root and refresh to stop the cooking.

Wash and slice the celery, keeping any leaves; wash the grapes and halve them lengthwise.

Peel the apple and slice very thin; keep the slices in cold water so they do not brown.

In a bowl, toss a few grapes, apple slices (patted dry), some celery and celery root with some of the dressing, keeping some of each undressed for garnish.

Lay large lettuce leaves on the plate, add the dressed salad, and garnish with the undressed apple, celery root, celery and candied walnuts.

Clean the plate and finish with a little baby watercress.