Heat up a waffle iron. Mix together the soy milk and vinegar in a small bowl and set aside. In a large bowl, wisk together the cornmeal, both flours, brown sugar, baking powder, salt and cinnamon until combined. Make a dent in the middle of the dry mixture and add the milk/vinegar mixture and the oil, continue to wisk until all the ingredients are thoroughly blended. Gently fold in your cooked pieces of tempeh so that they are evenly distributed in the batter. Open the pre-heated waffle iron and spray it with the coconut oil, then pour in about a 1/2 cup (depending on the size of waffle iron) of batter. Cook each waffle 3-4 minutes or until golden brown. Top each waffle with a couple of healthy spoonfuls of mushroom gravy.