Preheat oven to 350 degree F. Cut squash in half lengthwise; remove and discard seeds. Arrange the squash halves, cut sides down, in a 3-quart rectangular baking dish. Bake for 30 minutes. Turn squash halves cut sides up. Bake, covered, 20 to 25 minutes more or until squash is tender. Let cool slightly. Carefully scoop the pulp from squash halves into a medium bowl; discard shells. Mash squash slightly with a potato masher; set aside.
In a large saucepan cook onion in hot oil for 3 to 4 minutes or until tender. Add garlic and ginger; cook and stir 1 minute more. Carefully stir in mashed squash, chicken, broth, coconut milk, water, curry powder, salt, and pepper. Cook over medium heat until heated through, stirring occasionally.
To serve, spoon hot rice and bisque into bowls. Sprinkle with cilantro and cashews. Makes 5 or 6 servings.