1 1/2 cups wild rice (about 9 ounces)
2 teaspoons coarse kosher salt
3 cups 1/2-inch cubes peeled butternut squash (from 11/2-pound squash)
3 tablespoons olive oil
6 tablespoons (3/4 stick) butter, divided
1 1/2 cups finely chopped leeks (white part only)
1 1/2 cups frozen white corn kernels, thawed
1 tablespoon chopped fresh Italian parsley