Stuffing: Boil the potatoes in their jackets until very soft. Peel and mash them thoroughly. Add the remaining stuffing ingredients. Mix well and set aside. This filling can be prepared ahead and refrigerated for a day. There is no need to warm the stuffing before filling the bread.
To prepare the bread: Combine flours with salt in a bowl. Reserve about 1 teaspoon of shortening, and rub the remainder into the flour, with your finger tips until the mixture resembles coarse meal. Add most of the water to form a mass. Slowly add more water tablespoons at a time until dough forms. Brush the work surface and your hands with the reserved teaspoon of fat. Place the dough on the greased surface, and knead for 10 to 15 minutes. This will be a very soft and pliable dough. Put back in bowl and cover with a moist towel or a sheet of plastic wrap and let it rest, preferably in a warm place, for at least 1/2 hour.
Divide the bread dough and the filling into 12 equal portions. Take one piece dough and flatten it into a 4-inch round pillow with your hands. Depress the center slightly and place a portion of the filling into the depression. Bring the sides of the dough over the filling and enclose it completely. Press lightly but firmly to flatten it into a pillow, either between your hands or the work board. With your fingers, pinch the edges slightly, so that the filling is in the center and not near the edge where it could break through the dough. Cover with plastic wrap or a moist towel to prevent drying.
Pick up each pattie and dust with flour. Firmly pat the pattie to make filling adhere to dough. Roll out to a 6-inch circle dusting with flour as you go, to prevent sticking. Cover with plastic wrap or moist towel.
Heat the griddle or frying pan cook each bread for 2 minutes or until brown spots begin to appear. Flip the bread over and cook for 30 seconds. Brush lightly but thoroughly with melted shortening or oil and cook on original side for 30 seconds. Brush other side and flip again. Keep warm in a covered dish or tightly wrapped with foil. Note: They can also be made several hours ahead and reheated in a 300 degree oven for 10 to 12 minutes.