In the bowl of a standing mixer, pour warm milk, sugar and yeast. Let stand until yeast starts to foam, about 10 minutes. Attach dough hook to standing mixer. In a medium bowl, whisk together the flour and salt. Add flour mixture, butter and egg yolks to the yeast mixture; beat on medium speed until it combines and forms a ball, about 3-5 minutes.
Cover bowl and allow dough to rise in a warm place for 1 hour. Spray a sheet tray with non-stick cooking spray; set aside. Transfer dough to a lightly floured work surface; roll out to a 1/2" thickness. Using a 2"-3" donut cutter, cut donuts and transfer them and their holes to prepared baking sheet, spacing them 1" apart. Spray tops of donuts and holes with nonstick cooking spray; cover with plastic wrap. Let donuts stand in a warm place until almost doubled in size, about 30 minutes.
Using a deep fryer, heat oil to 350ºF. Line a baking sheet with paper towels; set aside. Working in batches, fry donuts and donut holes until lightly golden brown, about 1 minute per side. Transfer to baking sheet; let cool for 10 minutes before glazing.
Glaze:
Place sugar in medium bowl; slowly whisk in juice until desired consistency. Dip donuts into glaze or drizzle over donuts. Makes 12 servings.
Approximate Nutrient Analysis per serving:
250 calories, 6 g fat, 1 g saturated fat, 30 mg cholesterol,50 mg sodium, 46 g carbohydrate, 1 g fiber, 25 g sugar, 4 g protein