Sprinkle the yeast over the warm water and let stand until foamy, about 5 minutes.
In a large bowl of a stand mixer or using an electric mixer, mix together the yeast mixture, milk, sugar, shortening, salt, eggs and 2 cups flour. Mix for a few minutes at low speed, or stirring with a wooden spoon.
Beat in remaining flour 1/2 cup at a time, until the dough no longer sticks to the bowl. Knead until smooth and elastic, about 5 minutes Place the dough into a greased bowl and cover. Set in a warm place to rise until doubled in size. The dough is ready if you touch it and the indention remains.
Turn the dough out onto a floured surface and gently roll out to 1/2-inch thickness. Cut with a floured donut cutter. Let the donuts sit out to rise again until doubled in size. Cover loosely with a cloth.
Heat the shortening in a deep-fryer or large heavy skillet to 370 degrees F. Slide the donuts into the hot oil using a wide spatula. Turn the donuts over as they rise to the surface. Fry on each side until golden brown. Remove from the oil and drain on a wire rack.
While hot, dip the donuts into Maple Glaze, then into bacon pieces and set onto wire racks to drain off excess.
Mix 2 cups sugar, corn syrup, maple syrup, maple extract and salt into mixer. Mix well, 15 to 20 minutes. Add additional cup of powdered sugar to get to desired thickness. You may also add additional maple extract for desired taste.