Prep your oven and pan. Position a rack in the center of the oven and preheat the oven to 350°F. Spray a 9 x 5-inch loaf pan with cooking spray and line it with parchment paper, leaving a 2-inch overhang on the long sides. Spray the parchment, too.
Whisk the dry ingredients. In a medium bowl, whisk together the flour, cardamom, cinnamon, ginger, cloves, nutmeg, baking powder, baking soda, and salt.
Whisk the wet ingredients. In another medium bowl, whisk together the pumpkin, oil, vanilla, sugar, and eggs.
Make the muffin batter. Gradually mix in the dry ingredients into the wet ingredients until just combined.
Assemble the loaf cake. Pour the batter into the prepared pan and use an offset spatula to smooth the top. Sprinkle with the remaining sugar for the garnish.
Bake the loaf cake. Set the loaf pan on a sheet pan and bake for 60 to 70 minutes, or until a skewer inserted into the center of the cake comes out with a few crumbs attached. There will still be patches of sugar on top, but that’s totally okay, I promise! In fact, that’s the look you want. Cool on a wire rack.
Serve and store. Serve warm or at room temperature. The cake can be stored at room temperature, wrapped tightly in plastic wrap, for up to 3 days.