Mix cereal and boiling water together in a metal bowl, and allow to cool.
Cream shortening, sugar, and eggs in a large bowl. Add buttermilk and cooled cereal mixture. Combine flour, baking soda, and salt; stir into the creamed mixture until flour is moistened. Batter should be lumpy. Put batter into a one gallon wide mouth jar. When using mix, use a ladle to get batter out of the jar; don’t mix or stir.
When ready to use, spoon batter into muffin tins. Bake at 375 degrees F (195 degrees C) for approximately 15 minutes.