1In a large bowl, add boiling water to the first 6 cups of bran cereal, cool.
2Cream shortening or margarine, sugar, eggs, and buttermilk together. Add to bran mixture. Stir in flour, baking soda, and salt. Fold in the 12 cups of bran cereal. Stir only until moistened.
3Bake in a preheated 425 degree F (220 degree C) oven for 20 to 25 minutes.