Preheat oven to 350°F.
Using a hand mixer, combine the melted butter, sugar, vanilla and pumpkin.
1/2 cup salted butter, 1 1/2 cups granulated sugar, 1 1/2 tbsp vanilla, 1 cup pumpkin puree
Mix in the eggs and milk.
2 eggs, 1 tbsp milk
Add the flour, soda, salt, cinnamon and pumpkin pie spice to the bowl and mix until combined. The batter will be soft.
2 cups all-purpose flour, 1 tsp baking soda, 1 tsp salt, 1 tsp cinnamon, 1/2 tsp pumpkin pie spice
Fold in the chocolate chips. Spread the dough on to a greased half sheet cookie pan (18x13in).
2 cups chocolate chips
Bake for 15-20 minutes or until the top is no longer glossy and it passees the toothpick test.
Allow the bars to cool on the pan. Cut and serve.