Prep: Preheat the oven to 350°F (175°C). Grease a 9x5 inch loaf pan or line it with parchment, leaving some overhang so you can lift the loaf out easily.
Mix the wet ingredients: In a large bowl, whisk the pumpkin puree, melted butter, dark brown sugar, and granulated sugar until combined. Whisk in the eggs and vanilla until smooth.
Add the dry ingredients: Sprinkle the flour, baking soda, salt, and pumpkin pie spice over the wet mixture. Fold with a spatula until just combined with no dry flour left.
Fold in the chocolate chips: Fold in 1 cup of chocolate chips. Save 1/2 cup to sprinkle on top if you want a prettier loaf.
Fill the pan: Pour the batter into the prepared pan and smooth the top. Sprinkle on the reserved chocolate chips.
Bake: Bake for 60 to 70 minutes, until a toothpick inserted in the center comes out clean or with a few moist crumbs (not wet batter). If the top is browning too fast, tent it loosely with foil for the last 15 to 20 minutes.
Cool: Let the bread cool in the pan for 15 minutes, then lift it out and cool on a wire rack. Slicing while it’s still hot makes the crumb gummy, so try to wait.