In a large mixing bowl, whisk together the 2 cups all-purpose flour, 1/2 cup granulated sugar, 2 tsp baking powder, 1/2 tsp baking soda, 1/2 tsp salt, and n1/2 tsp ground nutmeg.
2 cups all-purpose flour, 1/2 cup granulated sugar, 2 tsp baking powder, 1/2 tsp baking soda, 1/2 tsp salt, 1/2 tsp ground nutmeg
In another bowl, whisk together the 1/2 cup buttermilk, 2 large eggs, melted 2 tbsp unsalted butter, and 1 tsp vanilla extract until well combined.
1/2 cup buttermilk, 2 large eggs, 2 tbsp unsalted butter, 1 tsp vanilla extract
Pour the wet ingredients into the dry ingredients and stir until just combined. The dough should be soft and slightly sticky. Do not overmix.
Cover the bowl with a damp towel and let proof in a warm, dry place for 1 hour.
On a lightly floured surface, roll out the chilled dough to about 1/2 inch thickness. Use a floured donut cutter or two differently sized round cookie cutters (one larger for the donut and one smaller for the hole) to cut out the donuts. Gather and re-roll the scraps as needed.
Lay the cut donuts on a baking sheet lined with parchment paper. Cover the pan with a damp towel and let proof a second time in a warm, dry place for 30 hour.
In a large, heavy-bottomed pot or deep fryer, heat Vegetable oil to 350°F (175°C). Use enough oil to submerge the donuts completely.
Carefully place a few donuts into the hot oil, being careful not to overcrowd. Fry for about 3 minutes per side, or until golden brown and cooked through. Use a slotted spoon or spider strainer to remove the donuts from the oil and place them on a wire rack lined with paper towels to drain excess oil. Repeat with the remaining donuts.
Vegetable oil
In a medium bowl, whisk together the 2 cups powdered sugar, 1/4 cup milk, and 1 tsp vanilla extractt until smooth. Adjust the consistency by adding more milk or powdered sugar as needed.
2 cups powdered sugar, 1/4 cup milk, 1 tsp vanilla extract
While the donuts are still warm, dip each one into the glaze, coating both sides thoroughly. Place the glazed donuts back onto the wire rack to allow any excess glaze to drip off.
Allow the glaze to set for a few minutes before serving.