Heat oven 300 F. Combine, in a big bowl, flours, cornmeal, milk powder and salt. Dissolve yeast in1/4 cup lukewarm water; let it sit for a few minutes, until it bubbles. Add the chicken broth to the yeast mixture. Mix well. Add the liquid to the dry ingredients. Knead about 3 min. The dough should be stiff. Flour a board with cornmeal and roll out the dough to a thickness of 1/4 inch. Cut out biscuits with a cookie cutter and place on ungreased cookie sheets. Mix the egg and milk and use to brush tops of biscuits (for shine). Bake at 300 F for 45 min. Turn off the heat and leave biscuits in the oven overnight. This will make the biscuits bone-hard. Hope Brandy likes these.