Amount of last 4 ingredients determined by number of squash. Precook squash by cooking in shallow pan with water until soft, approximately 1/2 hour in 350 degree oven.
Mix raisins, nuts, celery, apples in bowl with brown sugar, pancake syrup, pinch of pumpkin pie spice to taste. Mix well. Put butter in acorn squash. Stuff the acorn squash with mixture and put a little butter on top. Bake 1/2 to 3/4 hour at 350 degrees.