Preheat a dutch oven with lid in the oven at 425 degrees F.
Combine soy milk and apple cider vinegar and set aside.
Combine flours and baking soda.
Pour soy milk mixture into flour mixture.
Using your hands, combine until just mixed together.
Shape the dough into a disk, no more than 3 inches thick.
Place in the dutch oven and score the top with a razor blade or sharp knife.
Bake with the lid on for 30 minutes, then remove the lid and bake an additional 15 minutes.
Cool on wire rack for at least 30 minutes before serving.