combine stock, peas, carrots, and celery, season with salt, boil, simmer 10 minutes. Set aside. saute in 3 talbespoons butter, the onion, for 5 minutes. add rice, saute 2 minutes. add the vegetable mixture and chicken, season with pepper, boil, simmer 15 minutes, stir in dill and parsley, remove from heat and set aside. Mix remaining butter with milk and egg, brush a pie pan with this mixture. Place down one pie crust, brush with mixture, spoon in rice, cover with othe pie crust, brush with mixture and vent. Bake at 400 degrees for 15 minutes, lower heat to 350 and bake another 10 minutes or until top is golden brown.