Scalloped Potatoes with spinach

4 tablespoons butter 1/4 cup flour 2 1/2 cups milk 2 cups gruyere cheese , shredded and divided 1/2 teaspoon salt 1/2 teaspoon pepper 1 (10 ounce) package[...]

1 (10 3/4 ounce) can condensed cream of celery soup 1 (8 ounce) package spreadable cheese with garlic and herbs (such as Rondele) 1 1/4 cups milk 1 (16 ounce)[...]

4 tablespoons butter 1/4 cup flour 2 1/2 cups milk 2 cups gruyere cheese , shredded and divided 1/2 teaspoon salt 1/2 teaspoon pepper 1 (10 ounce) package[...]