In a mixing bowl, whisk together flour, granulated sugar, baking powder, and salt.

In another bowl, whisk together milk, egg, melted butter, and vanilla extract.

Gradually add the wet ingredients to the dry ingredients, stirring until a thick batter forms.

Heat oil in a deep skillet or pot over medium heat (about 350°F or 175°C).

Carefully drop spoonfuls of batter into the hot oil, frying a few at a time.

Cook for 1-2 minutes on each side until golden brown and cooked through.

Use a slotted spoon to remove the bites and drain on paper towels.

In a small bowl, mix granulated sugar and cinnamon.

While still warm, roll each donut bite in the cinnamon-sugar mixture until well coated.

Serve immediately and enjoy!