Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan thoroughly with non-stick spray or butter.

In a large mixing bowl, whisk together the dry ingredients: flour, baking powder, baking soda, salt, cinnamon, nutmeg, and ginger.

In another bowl, blend together the wet ingredients: granulated sugar, brown sugar, vegetable oil, eggs, pumpkin puree, and vanilla extract until smooth.

Gradually add the dry ingredients to the wet mixture, stirring gently until just combined.

In a small bowl, whisk together the swirl ingredients: powdered sugar, honey, cinnamon, and milk until smooth and pourable.

Pour half of the pumpkin batter into the prepared baking pan, drizzle half of the swirl mixture over it, then gently swirl it into the batter. Repeat with remaining batter and swirl mixture.

Bake for about 30 to 35 minutes, or until a toothpick inserted comes out clean.

Let the cake cool in the pan for about 10-15 minutes before transferring it to a wire rack to cool completely.