Preheat your oven to 350°F (175°C) and grease a donut pan.

Whisk together the dry ingredients in a large bowl: all-purpose flour, cocoa powder, granulated sugar, baking powder, and baking soda.

Mix the wet ingredients in another bowl: combine the eggs, vegetable oil, buttermilk, red food coloring, and vanilla extract until smooth.

Combine the wet and dry ingredients gradually. Stir until just mixed, being careful not to over-mix.

Spoon the batter into the donut pan, filling each cavity halfway.

Bake for 12-15 minutes, or until a toothpick inserted comes out clean. Let cool before glazing.