Preheat oven to 350°F (180° C). Grease and flour a 9 x 9-in. (23 X 23-cm) baking pan or 9 x 5-in. (1.9-L) loaf pan.
In a medium bowl, sift together flour, pumpkin pie spice, baking powder, baking soda and salt. In a separate bowl, using an electric mixer (stand or hand-held), cream together butter and sugar until smooth. Gradually beat in eggs one at a time then stir in pumpkin puree, vanilla and milk. Fold wet ingredients into dry. Stir in chocolate chips; pour batter into prepared pan.
If using the square pan, bake on middle rack of oven 35 to 45 min. If using the loaf pan, bake on middle rack 45 to 55 min., or until a toothpick inserted into centre comes out clean or picks up only a few moist crumbs.