5 pounds all-purpose unbleached flour (I use King Arthur flour)
1 cup raw wheat germ
3/4 cup baking powder
3/4 cup sugar
2-3 tablespoons salt
1 tablespoon cream of tartar
Put about two-thirds of the flour into a really large mixing bowl, add remaining ingredients. Using a wire whisk, stir together well. Add remaining flour and stir together well again to make sure everything is evenly distributed.
I store mine on the counter in a large, wide-mouth jar. If you don't think you will use it all up in about a month, store part in the fridge or the freezer so the baking powder doesn't lose its effectiveness.
Recipe source: http://lazyjbarcfarm.blogspot.com/