Chicken picardy with dill sauce

4    Boneless skinless chicken br
      4    Spinach leaves
      4    Leeks
      4    Shallots; finely chopped
      8 md Fresh mushrooms; finely chop
      1 pn Salt; to taste
      1 pn White pepper; to taste
  1 1/2 c  chicken stock; in baking pan
      4 fl White wine
      1 c  Leeks (green part only); sli
 
  Recipe by: Marcel Kerval of Cafe de France, St. Louis, MO
  Preparation Time: 0:40
  NOTE: This recipe calls for Marcel Kerval's dill sauce. Please see the
  recipe for "Dill Sauce for chicken Picardy" to complete these
  directions.
  
  TO PREPARE chicken PICARDY:
  Pre-heat oven to 375 degrees F. Prepare eight squares of aluminum foil by
  cutting foil into sheets (6" x 6") and buttering them lightly on the
  shiny side.
  
  Bone and skin chicken breasts. DO NOT HALVE. Flatten breasts between
  sheets of waxed paper with knife edge and place each breast on a square
  of foil.
  
  Soak leeks. Separate and rinse well under running water to remove sand.
  Finely slice green portion, allotting 1/2 green portion of a leek to each
  breast. Chop mushrooms, spinach leaves, and shallots, allowing 2
  mushrooms per portion.
  
  Saute this mixture very briefly (about 30 seconds) in a little butter
  over medium heat. Place 1/4 of mixture on each breast. Splash about 1
  ounce white wine over each breast, salt and pepper to taste, and roll up
  each breast.
  
  Seal each breast in an aluminum foil square. Fold ends tightly to seal.
  Place prepared chicken into a baking pan filled with 2 or 3 inches of
  chicken stock and bake in a pre-heated oven for 25 minutes.
  
  Saute cup of sliced leeks in butter over medium heat.
  
  TO SERVE: Unwrap chicken breasts and slice into 1/4-inch rounds. Pour a
  portion of dill Sauce on a plate. Lay chicken rounds over sauce and
  garnish with sauteed leek slices and serve.