Preheat oven to 350° F.
Cream butter and sugars together until light and fluffy. Beat in eggs, pumpkin and vanilla.
In a separate bowl, mix together flour, pumpkin pie spice and baking powder. Add to creamed mixture and mix well. Stir in nuts and chocolate chips if desired.
Drop by teaspoonfuls onto a well-greased cookie sheet. Bake for 15 minutes, or until lightly browned. Remove from cookie sheet and cool on rack.