Preheat oven to 350 degrees F. Spray doughnut pan/s with pan spray generously and set aside.
In a large bowl, whisk together the dry ingredients. In a separate bowl, whisk together the buttermilk, melted butter, vanilla, distilled vinegar, and eggs. Gently fold the wet mixture into the dry ingredients. Be careful not to over-mix. Too much stirring and folding will cause the donuts to be tough and dense. Fold in the red food coloring and stir until combined.
Spoon the donut batter into the prepared doughnut pan/s, and bake for 13-16 minutes, or until the doughnuts spring back when pressed lightly on top. Allow doughnuts to cool a few minutes in the pans and then transfer to a wire rack to cool completely.
In the bowl of a stand mixer or in a large bowl with a hand mixer, beat the cream cheese, butter, and vanilla extract on medium speed until completely smooth. Reduce the speed to low and gradually add the sifted powdered sugar. Add in the milk one tablespoon at a time. If you want to spread the frosting on the donuts, you will only use about 2 tablespoons of milk. If you want a thinner glaze, add more milk, one tablespoon at a time until it is smooth and dippable.
Spread the frosting on the cooled donuts with an offset spatula or dip into the thinner icing and add sprinkles.
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Notes
Using Gel Food Coloring with a small amount of vinegar is the best way to get that gorgeous red color! You can leave the coloring out if preferred. The donuts will still taste delicious but will be a light to medium brown in color, depending on the color of your cocoa powder.