Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a mixing bowl, combine the dry ingredients: sugar, all-purpose flour, baking powder, and salt. Mix well and set aside.

In another bowl, whisk together the wet ingredients: egg, milk, melted butter, and pure vanilla extract until well combined.

Slowly pour the wet mixture into the dry mixture, stirring until a soft dough forms.

On a lightly floured surface, roll out the dough to a thickness of about 1/2 inch.

Use a donut-shaped cookie cutter to cut out the donuts, then transfer them to the prepared baking sheet, leaving some space between each donut.

Bake in the preheated oven for approximately 10 minutes or until the donuts are lightly golden.

While the donuts are cooling, prepare the vanilla frosting. In a mixing bowl, combine powdered sugar, milk, and vanilla extract. Mix until you achieve a smooth, pourable consistency. Adjust the milk or sugar as needed to get the desired thickness.

Once the donuts have cooled for about 20 minutes, dip the top side of each donut into the vanilla frosting, allowing any excess to drip off.

Place the frosted donuts on a wire rack to set for about 10 minutes.

While the frosting is still tacky, get creative and customize your donuts with toppings like sprinkles, crushed nuts, mini chocolate chips, or a drizzle of icing. Let your imagination run wild!