01 - Preheat oven to 350°F. Grease a 9×5-inch loaf pan and line with parchment paper, leaving an overhang on the long sides for easy removal.
02 - In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, salt, and ground cinnamon until evenly distributed.
03 - In a separate bowl, whisk the eggs, whole milk, melted cooled butter, and vanilla extract until smooth and well blended.
04 - Pour the wet mixture into the dry ingredients. Gently fold and stir until just combined — stop as soon as no dry streaks remain. Do not overmix.
05 - Scrape the batter into the prepared loaf pan and smooth the top with a spatula to create an even surface.
06 - Bake for 40 to 45 minutes, or until a toothpick inserted into the center of the loaf comes out clean. Tent loosely with foil if the top browns too quickly.
07 - Let the loaf cool in the pan for 10 minutes, then lift it out using the parchment overhang and transfer to a wire rack.
08 - While the loaf is still warm, brush the top and all sides generously with the melted butter for the topping.
09 - In a small bowl, mix the granulated sugar and ground cinnamon for the topping. Sprinkle and gently pat the mixture over the buttered surfaces, ensuring complete and even coverage.
10 - Allow the loaf to cool completely on the wire rack before slicing into 8 even portions. This ensures the cinnamon sugar crust sets properly.