Preheat oven to 400 degrees F and grease a 9x9 inch pan.
Place cubed potatoes in the bottom of the greased pan.
In a bowl, mix milk, cream, flour, salt and pepper. Pour over the potatoes. Top with the shredded cheese and then tightly cover the dish with foil. Bake for 30 minutes.
Meanwhile, crush the cornflakes and after the potatoes have cooked 30 minutes, remove the potatoes from the oven, sprinkle with crushed cornflakes and drizzle with butter. Bake uncovered for 20-25 minutes until golden and the potatoes are tender.