1Heat oven to 350ºF. In 11x7-inch microwavable dish, spread squash cubes. Add water; sprinkle with salt. Cover with plastic wrap, folding back one edge or corner 1/4 inch to vent steam. Microwave on High about 5 minutes or until squash is crisp-tender.
2Meanwhile, in medium bowl, mix remaining ingredients with spoon. Sprinkle evenly over squash.
3Bake uncovered 40 to 45 minutes or until streusel is brown.