4cups(about 227g)wheat bran flakes or plain wheat bran
2cups(about 113g)bran buds, (look like little pebbles) or all-bran (look like little twigs)
4cups(1 quart) buttermilk, (or equal parts sour cream and milk whisked together)
½cup(113g)salted butter, melted
5cups(about 710g)whole wheat flour
In a large bowl with a tight fitting lid (needed if you aren't baking the muffin batter right away), add the wheat bran flakes or wheat bran and the bran buds or all-bran.
Pour the boiling water over the top, and mix well. Stir every couple of minutes while the mixture cools to room temperature. The mixture will be thick and sticky; it's ok if there are a few dry patches.
After the mixture cools to warm room temperature, add the buttermilk, melted butter, applesauce, sugar, eggs and vanilla. Mix well.
Add the flour, baking soda and salt. Stir until ingredients are combined.
The batter can be baked right away or stored in the refrigerator, covered well, for up to a month to bake as needed. Give the batter a good stir before using if it has been refrigerated.
To bake, scoop the batter into greased or lined muffin tins, filling 3/4 full. Bake at 375 degrees (350 degrees for dark coated muffin tins) for about 14-16 minutes, until a toothpick inserted in the center of a muffin comes out clean or with a few moist crumbs.