Fastnachts are a Pennsylvania Dutch Shrove Tuesday tradition. In the small Pennsylvania town where I grew up, my great aunt Mary Klinedinst made dozens of these fat doughnuts every year for friends and family. Her fastnachts were famous. One year, while living in San Francisco, I decided to share the pre-Lenten tradition with friends and colleagues. Per Aunt Mary's recipe, I mixed up my fastnachts the night before Shrove Tuesday. They rose and rose and rose some more, and I ran out of room in my small apartment for the second rising. At 5 am the next morning, I got up and started frying donuts. After three hours, I sent my roommate to our offices with two shopping bags of freshly made donuts. I kept frying donuts for two more hours and then took two more shopping bags to work. I never understood how Aunt Mary was able to make dozens of fastnachts every year well into her 80s, even with her daughters' help. They are delicious, though.
Mix in the evening. Grease top to keep soft and cover tightly. Set in a warm place to rise overnight. In morning, form fastnachts with greased hands, forming a center hole with your thumbs. Let them raise again and fry in deep vegetable shortening, rounded side down for a perfectly rounded product.* Drain well on absorbent paper and roll in granulated sugar. Makes about 5 dozen (large) fastnachts.
*Shortening must be heated to the point at which a bread cube fries to a golden brown and kept at that temperature. If the fat is too hot, the fastnachts will be too hard.