Preheat & Prep: Preheat the oven to 350°F (175°C) and grease a donut pan.
Mix the Dry Ingredients: In a large bowl, whisk together flour, sugar, baking powder, nutmeg, and salt.
Combine the Wet Ingredients: In a separate bowl, mix buttermilk, beaten eggs, vanilla extract, and melted butter until smooth.
Make the Batter: Gradually add the wet ingredients to the dry ingredients, stirring gently until just combined.
Fill the Donut Pan: Spoon or pipe the batter into the greased donut wells, filling each about two-thirds full.
Bake: Bake for 8–10 minutes until a toothpick inserted in the center comes out clean.
Cool the Donuts: Let them cool in the pan for a few minutes, then transfer to a wire rack.
Make the Glaze: In a small bowl, whisk powdered sugar, milk, and vanilla extract until smooth.
Glaze the Donuts: Dip each cooled donut into the glaze, letting the excess drip off. Set on a wire rack to dry before serving.