Proof the Yeast:

Proof the yeast: Stir yeast into warm milk and let sit roughly 5 minutes until bubbly.

Mix Dry Ingredients:

Mix dry ingredients: In a large bowl, combine flour, sugar, and salt. Add softened butter, eggs, and the proofed yeast mixture. Blend until a sticky dough forms.

Knead the Dough:

Knead: Transfer dough to a floured work surface and knead 5–10 minutes until smooth and elastic.

First Proof Dough:

First proof: Put dough in a greased bowl, cover with a damp towel, and let rise in a warm, draft-free spot for 1–2 hours until doubled in size.

Shape Donuts:

Shape donuts: Roll dough to about 1/2 inch (1.25 cm) thickness. Use a donut cutter or a large glass with a smaller cutter to cut out donuts. Gather and reroll scraps, then cut again.

Second Proof Donuts:

Second proof: Arrange cut donuts on a parchment-lined baking sheet, cover loosely, and let rise 30 minutes until puffy.

Fry Donuts:

Fry: Heat vegetable oil in a deep fryer or heavy pot to 350°F (175°C). Fry donuts in batches, 1–2 minutes per side, until golden. Transfer to paper towels to drain.

Finish with Sugar:

Finish: Sprinkle warm donuts with powdered sugar.