Preheat oven to 350°F (175°C).

Grease a 11x7 inch baking dish.

In a bowl, stir together crushed cornflakes cereal and melted butter.

Spoon half of the cornflake mixture into the prepared baking dish.

Top with shredded angel hair cabbage and thinly sliced sweet onion.

In a separate bowl, stir together milk, mayonnaise, and cream of celery soup.

Pour the milk mixture over the cabbage and onion layer.

Sprinkle with shredded sharp Cheddar cheese and the remaining cornflake mixture.

Cover the baking dish with foil.

Bake in the preheated oven for 1 hour.

Let cool slightly before serving.