Drain Veg-All.

Chop water chestnuts, celery, and onion.

In a large bowl, mix Veg-All, mayonnaise, chopped water chestnuts, chopped celery, chopped onion, cream of celery soup, and 3/4 cup grated sharp cheese.

Place the mixture in a 9 x 13-inch baking pan.

Chill the casserole overnight.

Preheat oven to 350°F (175°C).

Bake the casserole for 30 minutes or until heated through.

Remove from oven.

Crush Ritz crackers.

Melt butter or margarine.

In a separate bowl, mix crushed Ritz crackers, melted butter, and remaining grated sharp cheese.

Top the casserole with the cracker crumb mixture.

Bake until the topping is brown.