Here is one recipe I found, there are also several others at berksweb.
www.berksweb.com/pam/fast.html
Fastnachts
12 Doughnuts

1 envelope dry yeast
1 cup warm water
1/2 cup flour
5 1/2 cups flour
2 cups whole milk
1 tablespoons sugar
1/2 cup sugar
salt
3 eggs, beaten
4 tablespoons butter, softened
pinch nutmeg

Proof yeast in 1 cup warm water. Add 1/2 cup of the flour, stirring
until smooth, then add milk.

To the mixture, add 1 tablespoon sugar and 5 1/2 cups of flour,
blending well. Cover and let rise until doubled in bulk. Mix in
the salt, eggs, butter, nutmeg and 1/2 cup sugar. Knead in enough
extra flour in order to make a firm dough.

Let rise again until doubled. Punch down and roll out on a floured
board. Cut into squares. Cover and let rise for 20 minutes.

Preheat the oil in the deep fryer. Fry donuts until golden brown.
Drain on paper towels. Dust with powdered sugar while still warm.