Preheat oven to 350°F. Grease a 9x5-inch loaf pan with cooking spray. Then, line the pan with parchment paper, leaving a 2-inch overhang on each side so you can remove the bread easily from the pan.
Combine the flour, pumpkin pie spice, baking soda, baking powder, and salt in a large bowl. Set aside.
In a separate bowl whisk granulated sugar, brown sugar, sour cream, vegetable oil, and eggs until smooth. Whisk in pumpkin until smooth.
Pour the wet ingredients into the dry ingredients, and fold with a rubber spatula or wooden spoon until only a few streaks of flour remain. Fold in chocolate chips (only the regular-sized ones) until just combined.
Pour the batter into your prepared (greased and lined) loaf pan, spreading into an even layer if needed. Sprinkle a desired amount of miniature chocolate chips over the top of the batter.
Bake for 45 to 50 minutes, or until a toothpick inserted into the center of the loaf comes out clean. The center should spring back when you press on it gently.
Cool completely in the pan before transferring to a rack, slicing and serving.