Butternut Squash Gratin without pine cookies

1 (2 -3 lb) butternut squash 2 tablespoons unsalted butter 3 cups halved and sliced onions salt 1/4 teaspoon black pepper 3 cups peeled peeled cored sliced[...]

1/4 cup unsalted butter 4 cups thinly sliced onions (about 1 pound) 2 1/2 lbs butternut squash , peeled, seeded, cut into 1/2-inch cubes 1 teaspoon sugar 1/2[...]

1 -2 medium butternut squash 2 tablespoons olive oil 2 (14 ounce) cans diced canned tomatoes (plain or with basil, oregano) 2 cups cheddar cheese , shredded 1[...]