Step 1

Preheat the oven to 350F. Grease and flour two 8" or 9" (round) layer-cake pans or a 9x12" pan.

Step 2

Sift together the cocoa powder and flour. Set aside.

Step 3

Place the sauerkraut in a medium bowl. To this, add the egg yolks and water and mix thoroughly.

Step 4

In a large bowl, cream the butter and sugar.

Step 5

Add the vanilla and egg whites to the creamed mixture and mix thoroughly.

Step 6

Alternating between the wet (sauerkraut) and dry (flour) ingredients, add these to the creamed mixture, making sure to combine thoroughly before switching.

Step 7

Combine the baking powder, baking soda, and salt in a small bowl and fold it quickly into the creamed mixture.

Step 8

Pour the batter in the pan and bake for 30 minutes, or until a toothpick comes out clean.