In a medium pot cook onion, celery, butter and spices for 2 ½ minutes on medium heat. Add in cranberries and cook for another 2 ½ minutes. Pour in chicken stock and bring to a simmer. Add oats, reduce heat and cook for 1 minute. Remove oatmeal from heat and stir in egg. Pour mixture into a lightly greased 8-inch baking dish. Bake for 20 minutes covered. Remove cover and bake for an additional 25 minutes.