Barley Squash Gratin

3 pound butternut squash, peeled, halved, seeded, and cubed (about 5 cups)
15 – ounces spinach, chopped
1 large onion, sliced
1 1/2 cups regular barley (not quick-cooking)
1 1/2 cups broth, vegetable or chicken
3/4 cup water
1/2 teaspoon ground black pepper
3/4 cup shredded Parmesan cheese (3 ounces)

In a 6-quart slow cooker, stir together squash, spinach, onion, barley, broth, the water, garlic, and pepper.
Cover and cook on low-heat setting for 6 to 7 hours or on high-heat setting for 3 to 3-1/2 hours.

If possible, remove ceramic liner from cooker or turn off cooker. Sprinkle squash mixture with Parmesan cheese. Let stand, covered, for 10 minutes before serving at our potluck!