In a bowl, stir the warm water, yeast and a pinch of sugar and activate them
In the bowl of your stand mixer or in a large bowl put flour, milk, sugar, salt, eggs, vanilla and the yeast
Mix until combined for about 3-4 minutes
Cover with a cloth or plastic wrap and let it rest at room temperature for 10-12 minutes
Knead the dough by stand mixer or hand
Add 2-3 pieces of room temperature butter to the dough and continue to knead for 12-15 minutes
Cover the dough with a plastic wrap and keep it in the refrigerator overnight (or around 3 hours if short on time)
Put the dough on a floured counter and roll with a rolling pin to ½ inch thick
Using a circle cookie cutter cut the dough into pieces weighing 65-70g each
Place pieces on a parchment lined baking tray
Cover with a clean kitchen towel and let it rest at room temperature for 30-45 minutes (40-45 minutes if refrigerated overnight, 25-30 minutes if only 2-3 hours)
Heat the oil to 350F
Fry both sides until golden brown
Remove donuts from oil
Dip into the sugar and cinnamon mixture
Using a pastry bag fill with Nutella
