Glazed Doughnuts

Directions

1. Place potato in a medium saucepan; add water to cover. Bring to a boil. Reduce heat; cook, uncovered, until tender, 8-10 minutes. Drain potatoes; return to pan. Mash until very smooth.
2. In a large bowl, dissolve yeast in warm water. Add milk, butter, potato, eggs and, if desired, extract. Add sugar, salt, cinnamon and 3 cups flour. Beat until smooth. Stir in enough remaining flour to form a soft dough. Cover and let rise in a warm place until doubled, about 1 hour.
3. Stir down dough. On a well-floured surface, roll out to 1/2-in. thickness. Cut with a floured 2-1/2-in. doughnut cutter. Place on greased baking sheets; cover and let rise for 45 minutes.
4. Meanwhile, for glaze, combine 6 tablespoons milk, coffee and vanilla; stir to dissolve coffee. In a large bowl, beat butter, sugar, cinnamon and salt. Gradually add milk mixture; beat until smooth, adding milk to reach a good dipping consistency.
5. In an electric skillet or deep-fat fryer, heat oil to 375°. Fry doughnuts, a few at a time, until golden, about 1-1/2 minutes per side. Drain on paper towels. Dip tops in glaze while warm.