Saute onion and celery in bacon drippings about 5 minutes. Add butter, soup and milk. Stir in Velveeta and let melt. Place broccoli in a buttered 1 1/2 casserole dish. Stir rice into cheese mixture and then pour over the broccoli.
Bake at 350 degrees for 30 minutes or until broccoli is tender and lightly browned.