Cut squash in half crosswise, and remove seeds.
Cut bottom of each squash half to sit flat, if necessary.
Place squash halves, cut side up, in a 13- x 9- x 2-inch baking dish.
Add hot water to dish to depth of 1 inch.
Combine apple and next 3 ingredients; spoon evenly into squash halves.
Cover and bake at 350° for 1 hour or until squash is tender.
Sprinkle with pecans.