Here is the recipe, taken from this site:
1 and 1/4 cups flour, 1/2 cup cocoa powder, 1/2 cup salt, and 1/2 tablespoon cream of tartar in a large bowl.
While doing the dry ingredients, boil (don't skip this step) 1 cup water. Add 1 and 1/2 tablespoons vegetable oil to the boiling water and then turn heat to low. Add in dry ingredients and quickly mix. The mixture changes pretty rapidly. Pull dough out when a ball is formed and then knead the dough on wax paper.