01 - Preheat the oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - In a large bowl, whisk together the flour, sugar, baking powder, baking soda, cinnamon, and salt until well blended.
03 - In a separate bowl, whisk together the milk, eggs, melted butter, oil, and vanilla extract until smooth and fully incorporated.
04 - Pour the wet ingredients into the dry ingredients. Stir gently until just combined, being careful not to overmix.
05 - Transfer the batter to the prepared loaf pan and smooth the top evenly.
06 - Bake for 45-55 minutes, or until a toothpick inserted into the center comes out clean.
07 - Allow the bread to cool in the pan for 10 minutes, then carefully remove to a wire rack.
08 - While the bread is still warm, brush the top generously with melted butter. Mix the sugar and cinnamon in a small bowl, then sprinkle evenly over the buttered surface.
09 - Let cool completely for clean slices, or serve slightly warm for the best donut-like experience.