Disjoint chicken and cook in pressure cooker for 15 to 20 minutes along with parsley, bayleaf, onion, salt, peppercorns, and celery.
If you don't have a pressure cooker, you can use any large pot, and cook as long as necessary over medium heat until chicken is very tender.
Remove chicken, drain, and slice off meat, removing all skin.
Do not discard stock.
Keep chicken warm.
Skim fat from the stock, and reserve 1 cup.
In a heavy skillet, heat oil.
Stir in flour, and cook until brown.
Add 1 cup chicken stock and peas.
Cover and simmer 6 to 8 minutes.
Uncover, add milk, lemon juice and rind, salt and pepper.
Bring to boil, and reduce heat and cook until thickened.
On a large platter, place the mashed potatoes, rice, or noodles.
On top of that, arrange the warmed chicken, and top with the peas mixture.
Garnish with parsley.