Preheat the oven to 350°F
Grease a 9 x 5-inch loaf pan and line it with parchment paper, leaving a little overhang for easy removal.
Add the butter to a small saucepan over medium heat. Allow the butter to melt and continue cooking, stirring or swirling occasionally, until it begins to smell nutty and golden-brown milk solids form at the bottom of the pan.
Remove the browned butter from the heat and allow it to cool slightly.
In a large mixing bowl, add the pumpkin puree and eggs. Whisk until smooth and combined.
Add the granulated sugar, brown sugar, browned butter, and vegetable oil. Whisk again until smooth and fully combined.
Add the flour, pumpkin pie spice, cinnamon, baking soda, and salt.
Gently whisk or fold the dry ingredients into the wet ingredients just until a thick batter forms and no large streaks of flour remain. Do not overmix.
Add the 1 ½ cups semi-sweet chocolate chips and gently fold them into the batter until evenly distributed.
Transfer the batter to the prepared loaf pan and spread the top evenly.
Sprinkle additional chocolate chips over the top.
Bake at 350°F for approximately 1 hour, or until a toothpick or skewer inserted into the center comes out clean or with a few moist crumbs.
If the top begins browning before the center is finished baking, loosely cover the loaf with aluminum foil and continue baking.
Remove the pumpkin bread from the oven and allow it to cool in the pan for about 15 minutes.
Lift the loaf from the pan and transfer it to a wire cooling rack.
Allow the pumpkin bread to cool completely before slicing.