Over at Chickens in the Road, there is a quick mix that is used as a base for biscuits, muffins, and pancakes. I have modified it to fit our low sodium diet and used whole wheat flour.
5 cups whole wheat flour
1/4 cup Demerara Cane sugar
1/4 cup Hain Featherweight baking powder*
1 1/4 teaspoons Fruit Fresh citric Acid crystals **
Combine all ingredients in a large bowl and store like flour. I used a large container with a lid. The baking mix has 0 mg sodium.
* This baking powder is the key to the low sodium baking mix. It is made with potassium instead of sodium.
** The original baking mix calls for cream of tartar (tartaric acid), which contains a lot of sodium. I substituted citric acid crystals to help as a preservative (not that the baked goods last that long).