Preheat the Oven: Start by preheating your oven to 350°F (175°C) and greasing a 9x5 inch loaf pan.
Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, salt, ground cinnamon, and sugar.
Wet Ingredients: In a separate bowl, combine the milk, vegetable oil, egg, and vanilla extract. Whisk until fully blended.
Combine Mixtures: Gradually add the wet ingredients to the dry ingredients, stirring just until combined. Be careful not to overmix; a few lumps are okay!
Add to Pan: Pour half of the batter into the prepared loaf pan. Sprinkle a generous layer of cinnamon sugar on top. Then, add the remaining batter and sprinkle more cinnamon sugar on the top.
Bake: Bake for about 40-45 minutes, until a toothpick inserted into the center comes out clean. Let it cool slightly before slicing.
Enjoy!: Serve warm, drizzled with icing or all on its own!