PREPARATION:

1. Place flour and sugar in medium bowl; stir to combine. Make well in center of flour mixture; add egg yolks, sour cream and vodka. Stir with spoon until soft dough forms.
2. Place dough on lightly floured surface; knead gently until dough is smooth. Form dough into 2 discs; wrap in plastic wrap and refrigerate until firm, 30 minutes or overnight.
3. Working with 1 disc at a time, unwrap dough and place on lightly floured surface. Roll out dough with lightly floured rolling pin to 1/8-inch-thick (12X10-inch) rectangle. Cut dough lengthwise in half; cut each half into 12 strips.
4. Make 1-inch vertical slit down center of each strip. Insert one end of strip through cut to form twist; repeat with remaining strips.
5. Heat oil in large saucepan to 375°F. Place 6 strips at a time into hot oil. Fry about 1 minute or until golden brown, turning cookies once with slotted spoon. Drain on paper towels.
6. Place 1/3 cup powdered sugar in small brown paper bag. Add 6 warm cookies at a time; close bag and shake until cookies are coated with sugar. Repeat with additional sugar and remaining cookies. Cookies are best when served immediately, but can be stored in airtight container 1 day.