1. Preheat and Prep
I start by preheating my oven to 350°F (175°C). While it warms up, I grease my loaf pan with butter or nonstick spray. A light dusting of flour helps prevent sticking, too.

2. Mix Dry Ingredients
In a bowl, I whisk together the flour, granulated sugar, baking powder, and salt. No need to sift just break up any lumps with the whisk.

3. Combine Wet Ingredients
In another bowl, I mix the milk, egg, oil, and vanilla until smooth. Pro tip: Crack the egg into a small dish first to avoid shell surprises!

4. Bring It All Together
I pour the wet mixture into the dry ingredients and stir gently. A few lumps are okay! Overmixing makes the bread tough.

5. Layer the Swirl
Here’s the fun part! I spread half the batter into the pan. Then, I sprinkle most of the cinnamon sugar mixture (save 2 tablespoons for the top). Next, I add the remaining batter and smooth it out. Finally, I scatter the reserved cinnamon sugar over the loaf.

6. Bake to Perfection
The bread bakes for 50–60 minutes. To test doneness, I stick a toothpick into the center if it comes out clean, it’s ready. If not, give it another 5 minutes.

7. Cool and Slice
I let the bread cool in the pan for 10 minutes, then transfer it to a rack. Slicing too soon can make it crumble, so I try to wait at least 30 minutes (though it’s hard to resist!).