HOW TO MAKE CREAM-FILLED DOUGHNUT?
Mix yeast and milk in the bowl of an electric mixer with a dough hook attachment. Let sit for about a minute, or until the yeast is gone. Mix the flour, 1/3 cup sugar, salt, and eggs on low speed for about a minute, or until the dough comes together. Keep mixing on low for another two to three minutes. Add a few pieces of butter at a time, waiting to add more until the butter is fully mixed in and the dough is soft, about 5 to 6 minutes.
Take the dough out of the bowl and tightly wrap it in plastic wrap. Keep in the fridge for at least 6 hours and no longer than 15 hours.
Dust a baking sheet with a little flour and set it aside. On a well-floured work surface, roll out the dough until it is about 1/2 inch thick and 12 inches square. Cut out 9 doughnuts with a 3-1/2- to 4-inch round biscuit cutter. Transfer to the baking sheet you’ve already prepared and cover with plastic wrap. Let them sit in a warm place for 2 to 3 hours, or until they’ve doubled in size and feel soft and pillowy.