• Preheat oven to 400 degrees. Use a baking spray to prep your doughnut pan, and set aside. 
• Whisk together the flour, baking powder, baking soda, cinnamon, salt and sugar in a large bowl.
• Next, mix together the whole milk, sour cream, and eggs into a separate bowl. Then incorporate the melted butter, vegetable oil, and vanilla.
• Gradually whisk in the wet ingredients into the dry ingredients and stir just until combined.
• Divide the batter into three bowls. Add several drops of Yellow food coloring in the first bowl. Add several drops of Black food coloring in the first bowl. Leave the last bowl plain. 
• Spoon equal amounts of the 3 batters into the doughnut pan. Bake at 400 degrees for 9 minutes. Allow donuts to cool for a few minutes in pan and then transfer to cooling rack. 

Icing Directions

• Whisk together the milk, powder sugar and vanilla extract until smooth.
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• Split the icing into 2 bowls. Add yellow food coloring to one of the bowls. Then pour the yellow icing into the white icing, and do not stir.  

Assembly of Donuts

• Dip the donuts into the icing and turn the donut 90 degrees. Place the donut back onto the wire rack and repeat the previous steps for remaining donuts