Serve with thinly sliced black bread and a bowl of unsalted butter. Yield: 6 servings.

SAUCE VERTE:

2 eggs
1 egg yolk
1 tbsp. Dijon mustard
2 tsp. white wine vinegar
3/4 to 1 c. peanut oil
1/2 c. watercress leaves, blanched, drained and chopped
2-4 tbsp. finely minced fresh parsley (preferably Italian)
2-3 tbsp. cooked, drained and squeezed and chopped spinach
2-3 tbsp. finely minced fresh dill
2-3 tbsp. finely minced fresh chives
Salt and freshly ground white pepper
12 leeks
12 slices ham (preferably smoked)
Cherry tomatoes and parsley sprigs for garnish

Combine first 4 ingredients in processor or blender and mix until smooth. With machine running, slowly add oil in thin steady stream until mixture resembles mayonnaise. Add next 5 ingredients with salt and pepper to taste and mix until smooth. Cover and chill until ready to serve.

Trim leeks, leaving 2-3 inches of greens. Carefully slit outer layer and remove; wash and set aside. Slit remaining layers lengthwise (leaving leeks intact) and wash thoroughly. Rewrap in outer layer and tie with string. Let stand in ice cold water for 30 minutes.

Drain leeks well. Arrange in single layer in large saucepan. Add water to cover and season with salt. Bring to boil over high heat. Reduce heat and simmer until leeks are just tender. Drain on paper towels. Carefully remove string. Wrap each leek with ham and arrange seam-side down on rectangular serving platter. Spoon sauce evenly over top. Garnish with tomatoes and parsley.