Step 1: Preheat and prep
Preheat your oven to 350°F (175°C). Lightly grease a mini donut pan with non-stick spray or a thin brush of oil to ensure easy release after baking.

Step 2: Mix dry ingredients
In a medium mixing bowl, whisk together the flour, sugar, baking powder, baking soda, cinnamon, and salt. This dry mix is your flavor foundation — whisking helps evenly distribute everything.

Step 3: Combine wet ingredients
In a separate bowl or measuring cup, mix the buttermilk, egg, melted butter, and vanilla extract until smooth. Make sure your butter has cooled slightly so it doesn’t cook the egg when combined.

Step 4: Make the batter
Pour the wet ingredients into the dry mix. Stir gently using a spatula or spoon until just combined. The batter should be thick but smooth. Avoid overmixing to keep your donuts soft and tender.

Step 5: Fill the donut pan
Transfer the batter into a piping bag or a zip-top plastic bag with the corner snipped off. Pipe the batter into each cavity of the donut pan, filling about 2/3 of the way full. This gives the donuts room to rise without spilling over.

Step 6: Bake to golden perfection
Place the pan in the preheated oven and bake for 8–10 minutes, or until the tops spring back lightly when touched and a toothpick comes out clean. The bottoms should be just lightly golden.

Step 7: Cool slightly
Remove the donuts from the oven and let them sit in the pan for 2–3 minutes. Then carefully transfer them to a wire rack to cool slightly while you prepare the cinnamon sugar coating.

Step 8: Make the coating
In a small bowl, mix the granulated sugar and cinnamon until fully combined. In a separate bowl, melt the butter. This duo is what gives the donuts their signature crunch and spice.

Step 9: Coat the donuts
Once the donuts are cool enough to handle but still warm, dip each one in the melted butter, then roll it generously in the cinnamon sugar mixture. Make sure they’re fully coated on all sides for maximum flavor.

Step 10: Serve and enjoy
Arrange your cinnamon sugar mini donuts on a plate, platter, or just pile them into a bowl and start snacking. They’re best warm but still amazing at room temp.