In a large mixing bowl or the bowl of a stand mixer, combine all the ingredients. Mix until cohesive -- cover and set aside for 20 minutes, this will give the whole grains a chance to absorb some of the liquid. Then knead to make a smooth, soft, elastic dough.
Place the dough in a lightly greased bowl and let rise for 1~1½ hours or until the dough is noticeably risen, it will not double in volume.
Gently deflate the dough and divide into 12 equal size pieces. Shape each piece in to a round ball; using your fingers to pull and flatten each ball into a circle about 3" across.
Place the buns on a parchment lined (or lightly greased) baking sheet, cover and let rise for about 90 minutes, until noticeably puffy. Towards the end of the rising time, preheat the oven to 350°F.
Brush the rolls with soy or almond milk (or the egg white) and sprinkle with oats.
Bake the buns for 21~25 minutes or until they're golden brown. Remove from the oven and transfer to a rack to cool.
Once completely cooled, wrap the buns tightly and store at room temperature for several days or freeze for longer storage.