Donuts are SO fun. You should be excited. Let's go. In the bowl of a stand mixer add in sugar, baking powder, nutmeg, cinnamon, salt. Mix with the dough hook attachment until incorporated.
Next, in go the eggs, melted butter, vanilla, and milk. Mix until homogeneous.
Add flour slowly. Don't rush here. Once flour is incorporated turn off the mixture. If the dough feels too wet, sprinkle a bit of flour over it. If too dry add a tiny bit of milk. Form the dough into a disk, cover in plastic wrap and let chill in fridge for 30 minutes. The dough will keep 2 days in the fridge or 2 months in the freezer.
Heat oil in dutch oven or heavy bottomed pot to 360 degrees.
Pull dough from fridge and roll out to a sheet that is about 1/4 to 1/2 inch thick. Punch out dough into donut shapes.
Once oil is up to temperature, carefully lower the donuts into the hot oil. Don't crowd; you may only be able to do one or two at a time. Let them bubble away until side facing down is golden brown. Flip and brown the other side, about 5 minutes in total.
Once browned deeply, remove from oil and let drain on rack or paper towel. While still hot, drop donuts into a bowl that contains the sugar/cinnamon mixtured. Toss. EAT. EAT WHILE STILL HOT. YOU RARELY GET A CHANCE TO EAT A FRESH DONUT IN LIFE. DO IT NOW!!