Make the tangzhong first - Add milk to a saucepan over low heat. Warm for 3 minutes. Whisking constantly, add flour. Increase to medium low heat. Continue to whisk until a thick paste forms, about 4-6 minutes. The texture should be akin to a thick porridge. Pour into the bowl of a stand mixer and allow it to cool completely, about 30 minutes. 3/4 cup Whole Milk6 tbsp Bread flour
Once cooled and no longer hot to the touch, add warm milk, water, and yeast and 1 tbsp of sugar to a small bowl or cup. Whisk together and allow the yeast to bloom and become frothy, about 5-10 minutes. Add yeast mixture, egg, egg yolk, sugar to the tangzhong in the stand mixer. Gently whisk together until all ingredients are combined. 1/2 cup Whole Milk 2 tbsp Water2 1/4 tsp Active Dry Yeast1 tbsp Sugar1 large Egg1 Egg Yolk6 tbsp Sugar
Add bread flour, milk powder, nutmeg, and kosher salt. Gently use your hands or a rubber spatula to mix everything together to form a shaggy dough. Attach the dough hook to the stand mixer and mix on medium speed for 5 minutes. Then add room temperature butter, 2 tbsps at a time. Continue to mix on medium-high speed for 8-10 minutes. Dough should be smooth elastic. (If it sticks to the sides of the bowl, simply scrape the sides of the bowl and add pieces to the dough). Stand by the stand mixer, it'll begin to move/shake a little once it begins mixing on medium-high speed. 3 1/2 cups Bread Flour2 tbsp Milk Powder1/2 tsp Nutmeg1 tsp Kosher Salt 6 tbsp Salted Butter
Place dough into a well oiled large mixing bowl. Cover with plastic wrap and allow it to rise until doubled in size, about 1½-2 hours.
Punch dough down, then add to a lightly floured work surface. Use a rolling pin to roll dough out until it’s about a ½ inch thick. Use a 3 inch donut cutter or cookie cutter to press into the dough to form the donuts. Use the top of a piping tip to press a hole into the middle to form the center hole if your donut cutter doesn’t have a well in the center. Re-roll scraps and repeat until the dough is used up.
Place donuts onto a baking sheet and cover with plastic wrap or a clean kitchen towel. Allow the donuts to rise again in a warm place for about 30-45 minutes, until puffy.
Fill a large pot or dutch oven with oil over medium heat. Warm to 350-375 degrees F. Fry 2 donuts at a time - fry for about 2-3 minutes, flipping the donuts every 60 seconds. 4-5 cups Vegetable Oil
Remove from over and place onto a wire rack to drain the oil and repeat process with remaining donuts.
When you’re done frying, whisk together the glaze ingredients - powdered sugar, cocoa powder, warm water, and corn syrup. Dip the top of each of the donuts into the glaze and place back onto the wire rack to let the glaze set, about 10 minutes. 1 1/2 cups Powdered Sugar 4 tbsp Cocoa Powder4-5 tbsp Warm Water1 tbsp Corn Syrup
Notes
Use a kitchen scale if you have one. Yeast dough can change quite a bit when too much flour is added. Measuring the flour by weight gives you much more consistent results.
Make sure the tangzhong has cooled. Hot tangzhong can make the dough too warm and potentially interfere with your yeast.
Don't add extra flour. This is an enriched dough, so it may feel softer than you're expecting. Let the mixer knead it before deciding it needs additional flour.
Keep checking your frying oil. The temperature changes every time you add cold dough. Let it return to around 350°F before adding your next batch.
Glaze the donuts while they're slightly warm, not piping hot. If they're too hot, the glaze can become thin and run straight off.