1. Scoop out some of the squash into a bowl, leaving 1/4-inch thickness in the shells. Mash removed squash; add orange juice, brown sugar, and allspice. Stir well.
2. Cut a thin slice from bottom of each squash shell, so that it will sit ﬂat. Coat baking pan with oil or cooking spray and return squash to pan. Spoon mashed squash mixture into shells.
3. Combine corn ﬂake crumbs, pecans, and margarine. Sprinkle crumb mixture over squash.
4. Bake, uncovered, at 400 degrees Fahrenheit for 15 to 20 minutes or until heated through.