Preheat oven to 450°. Cut each squash in half through stem end; remove and discard seeds. Place squash, cavity side up, in large rimmed baking pan and add 1/4-inch water to pan; sprinkle squash with salt and pepper.
Place 1 tablespoon syrup, 1/2 tablespoon butter and 1/2 tablespoon brown sugar into each squash cavity. Sprinkle squash with herbs. Roast squash 1 hour or until very tender and golden brown, basting frequently with syrup inside cavities.