Step #1 In a large saucepan, herbs, nutmeg & half the celery, stock, juniper berries, onion, put chicken pieces, leek & carrot.
Step #2 If not already covered with stock, add water the cover the chicken pieces & let simmer until chicken falls off the bone (about 1 hr).
Step #3 Drain chicken & keep warm.
Step #4 Strain cooking liquid back into the saucepan.
Step #5 add in the remaining leek, carrot, celery & garlic & cook uncovered for 30 mins allowing stock to reduce to half the volume of strained liquid.
Step #6 Just before serving, remove chicken meat from bone.
Step #7 Mix together egg yolks, cornflour, & mustard.
Step #8 Slowly mix in lemon juice & rind.
Step #9 Ladle in a spoon at a time of reducing stock, stirring constantly until about 500ml is added, then pour this mixture back into reducing stock.
Step #10 Allow to thicken for a min or so.
Step #11 Arrange chicken on warm serving plate & pour over the thick sauce with its vegetables.
Step #12 Leftover potential: Keeps for two or three days in the refrigerator.