Preheat the oven to 400 degrees. Cut the squash in half lengthwise and scoop out the seeds. Discard any strings along with the seeds.
Place the cut side down in a 13-by-9-inch baking dish and add water to a depth of 1/2 inch. Cover with aluminum foil and bake 45 minutes to 1 hour or until tender. Drain and scoop out the pulp, discarding the outer shell.
In a large saucepan, combine the squash pulp, 2 tablespoons of the butter and 2 tablespoons of the brown sugar.
Blend with a potato masher until smooth. Stir in the raisins, salt, and nutmeg. Place over medium heat and cook 10 minutes, stirring often.
Meanwhile, in a small saucepan, combine the pecans, corn syrup and the remaining butter and brown sugar. Cook over medium heat 5 minutes or until the sugar dissolves.
Transfer the squash mixture into a serving dish and drizzle the candied pecan mixture over the top. Serve immediately.