1/4 cup plus 1 tablespoon (90g) unsalted butter at room temp
Notes
Dough was pretty sticky and I needed to add extra flour. After tablespoon after tablespoon, it never really became less sticky. At some point, use flour to just keep it from sticking to things and it'll be ok. It's just pretty sticky.
Directions
1. Take out eggs and butter early so they can come to room temperature.
2. Heat water to ~100F (shouldn't feel hot nor cold to touch).
3. Stir in yeast and set aside.
4. In a mixing bowl, measure out flours.
5. Add sugar and salt to bowl.
6. Attach a dough hook to a stand mixer and start it up with the flour mixture.
7. Pour in the water/yeast mixture.
8. Add the eggs and egg yolks
9. Once the dough comes together, add butter 1 tbsp at a time (do *NOT* add another until the dough incorporates the butter and comes back together).
10. After all the butter is added, wait 30s more.
11. Turn out to the counter and shape into a ball.
12. Place the dough in an oiled bowl and cover with a damp towel.
13. Wait 2 hours or until doubled in size.
14. Generously flour a work surface and turn out dough. Flour the top as well.
15. Roll the dough out to 1/2 inch thickness.
16. Use a 3in round biscuit cutter to punch out donuts and place on a well floured baking tray.
17. Cover and let proof for 1.5 hours.
18. Heat oil to 350F and fry in batches for 2-3 mins per side (or until brown).
19. Place on a wire rack to cool.
20. (Optional) When cool enough to touch but still warm/hot, dip donuts in sugar.
21. Use a chopstick to poke a hole to the middle of the donut and wiggle it gently to make a cavity.