Heat oil in a deep, 2-quart, heat-resistant, non-metallic casserole in the oven for 2 minutes.
Add onion and heat, uncovered, for 3 minutes or until tender.
Stir occasionally.
Add bay leaf, carrots, potatoes, salt, pepper, celery salt, beef gravy and beef [pre-cooked/boiled]; stir to combine.
Heat, covered, in Oven for 6 to 7 minutes.
Taste and correct seasoning, if necessary, with additional salt and pepper
Remove the bay leaf and discard.
Add peas and heat, covered, in Oven and cook for 2 to 3 minutes.
