Gently cook celery, onion, and carrots in chicken broth until just tender. Add the cornstarch mixture stir and cook a few minutes over moderate heat until thickened.Add peas, chicken and basil
Put mixture in wide casserole dish that just make the biscuits, mix the flour, salt and baking powder. Cut in the shortening with a pastry cutter or use your fingers to rub the flour and fat together until the mixture resembles coarse meal. Pour in milk and stir with a fork just until the dough kneads together. Knead 12 times about 30 seconds. Roll out on lightly floured surface.
Place biscuit on top of casserole mixture.Bake for 35 minutes or until biscuit topping is golden brown.