Homemade Amish Donuts

Learn how to make traditional Amish Fasnacht Donuts.
For the Sponge:
1 packet yeast
2 cups lukewarm water
4 scant cups sifted flour
For the Dough:
½ cup shortening
1/3 cup sugar
1½ teaspoons salt
2 eggs
½ teaspoon ground nutmeg
5 cups or more of flour