1) Preheat the oven to 350°F. Lightly grease a 9" x 5" loaf pan; or a 12" x 4" tea loaf pan.
2) In a large bowl, combine the oil, sugar, pumpkin, eggs, and molasses, beating until smooth.
3) Whisk together the baking mix and the pumpkin pie spice, then stir into the wet ingredients until evenly distributed; some lumps are OK.
4) Add the walnuts or chips, stirring just until distributed.
5) Spoon the batter into the prepared pan, smoothing the top. Let it rest at room temperature for 10 minutes.
6) Bake the bread for 40 minutes, then gently lay a piece of aluminum foil across the top to prevent over-browning.
7) Bake for an additional 15 to 25 minutes (10 to 20 minutes for the tea loaf pan). Remove the bread from the oven; a long toothpick or cake tester inserted into the center should come out clean, with at most a few wet crumbs clinging to it. The tester shouldn't show any sign of uncooked batter; if it does, bake the bread for an additional 5 minutes, or until it tests done.
8) Allow the bread to cool for 10 minutes in the pan. Remove it from the pan, and cool it completely on a rack.
Yield: about 18 servings.