• Preheat the oven to 350°F. Lightly grease two baking pans. Set aside.
• In a large bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon. Set aside these dry ingredients for later.
• Using a stand mixer (or in a large bowl using a hand mixer), cream the softened butter for 1-2 minutes, until creamy.
• Add the granulated sugar and light brown sugar, and cream together with the butter for 2-3 more minutes, until well combined and creamy.
• Beat in the vegetable oil, then the eggs, milk, and vanilla. Then add the milk. Cream until combined.
• Gradually add the dry ingredients to the wet ingredients and mix just until the ingredients are well combined. Take care not to over-mix in this step.
• You can then either scoop the batter into a piping bag and pipe the batter into the donut pans. Or, you can simply spoon the batter into the donut pans. Try to use an even amount for each donut.
• Bake at 350°F for 12-15 minutes, until a toothpick inserted into the center of a donut comes out clean.
• Dip a donut lightly into the melted butter. Then immediately dip it into the bowl of cinnamon sugar, coating both sides. Repeat with remaining donuts.

Optional chocolate glaze

• In a medium microwave-safe bowl, melt the chocolate and the coconut oil in a microwave in 30-second intervals, just until melted, whisking in between intervals.
• After coating the donuts in the cinnamon sugar, you can serve them next to the bowl of melted chocolate for people to dip donuts into. Or, you can transfer the melted chocolate to a small piping bag or a small ziplock bag with one corner cut, and drizzle lines of melted chocolate over the donuts.