Scalloped Potatoes with mustard

8 medium russet potatoes 1 yellow onion , coarsely chopped 4 tablespoons butter 4 tablespoons all-purpose flour 3 cups milk 1 lb Velveeta cheese , cubed and[...]

6 tablespoons unsalted butter 3 tablespoons all-purpose flour 1 3/4 cups heavy cream 2 teaspoons dry mustard 1 1/2 teaspoons salt 1 teaspoon dried thyme[...]

3 cups potatoes (very thinly sliced and peeled boiling potatoes) 1 teaspoon salt 2 tablespoons all-purpose flour 3 -6 tablespoons butter 1/4 cup chives[...]