01 - Preheat your oven to 350°F (175°C). Prepare a 9x5-inch loaf pan by greasing it and lining it with parchment paper for easy removal.
02 - In a medium mixing bowl, whisk together the all-purpose flour, baking soda, salt, pumpkin pie spice, and ground cinnamon until thoroughly combined.
03 - In a larger mixing bowl, vigorously whisk together the granulated sugar, vegetable oil, large eggs, canned pumpkin puree, milk, and vanilla extract until a smooth and homogenous mixture is achieved.
04 - Gradually incorporate the dry ingredients into the wet mixture. Stir gently until just combined, being careful not to overmix to ensure a tender crumb.
05 - In a small bowl, combine the packed light brown sugar, ground cinnamon, and melted unsalted butter for the swirl. Mix until a cohesive paste forms.
06 - Pour half of the prepared batter into the greased and lined loaf pan. Distribute half of the cinnamon swirl mixture in dollops over the batter. Use a knife to gently swirl the mixture into the batter. Repeat the layering process with the remaining batter and swirl mixture.
07 - Bake for 55 to 65 minutes, or until a wooden skewer or toothpick inserted into the center of the loaf emerges completely clean. If the bread begins to brown too rapidly, loosely cover it with aluminum foil.
08 - Allow the bread to cool in the loaf pan for 15 minutes before carefully transferring it to a wire rack to cool completely.
09 - While the bread cools, prepare the glaze by whisking together the powdered sugar, milk, and vanilla extract until a smooth drizzling consistency is achieved. Once the bread has cooled entirely, drizzle the glaze over the top before slicing.