Cook chicken breasts 1 hour - add 1 Tbsp. salt, 1 stalk celery, 3 slices onion, 10 peppercorns & 1/2 bay leaf. Let cool in broth. Remove chicken from bones & strain broth.
Heat 2 5/8 cup chicken broth. Mix 3/4 cup cooled broth with a scant 1/2 cup flour in shaker and add to boiling broth, cooking until thick. Cool.
Add mayonnaise, lemon juice & curry powder mixing until smooth.
Cook broccoli spears, drain well & place in buttered 9x13 pan. (Discard any tough stems and cut into smaller pieces.)
Add chicken and spoon sauce over smoothly.
Cover with grated cheddar cheese.
Brown bread crumbs in 1/4 cup margarine & sprinkle on top.
Bake at 375º for 50 minutes then cool for 10 minutes before serving.