Place Crisco, sugar and salt in the bowl of an electric mixer. Add 1/2 cup boiling water and stir until mixed. Pour in milk and allow to cool until lukewarm.
Dissolve yeast in 1/4 lukewarm water. When dissolved, add to yeast mixture. Add egg and stir.
Gradually beat in half of the flour; adding as much flour as remains until dough is no longer sticky. Turn dough out onto a lightly floured board and knead for several minutes until smooth and elastic.
Place dough in a lightly buttered bowl, turning over once to butter the top. Cover tightly and refrigerate immediately; do not allow to rise. Chill for 1 hour.
When ready to make donuts, heat 3-4 inches peanut or vegetable oil in a deep fryer to 375°F.
Meanwhile, roll out chilled dough to 1/4 inch thickness and cut into 2 1/2 inch squares using a sharp knife. (Don't do this step ahead of time because the dough shouldn't be allowed to rise before frying).
Lower donuts into hot oil several at a time. After about 2 minutes, turn the donuts over using a slotted spoon. Fry another minute, or until donuts are light golden brown.
Using a slotted spoon, remove donuts to paper towels. Sift confectioners' sugar over donuts while still warm.