Photo credit: One Hot Oven. Photo credit: One Hot Oven. Make sure to download this PDF Buttermilk guide to make 1/4 cup of buttermilk to 1 cup. Yogurt is tangy and acidic, like buttermilk.
With buttermilk powder, all you need is water. Mix about 1/4 cup of buttermilk powder with every 1 cup of water (or milk).