Preheat oven to 350°F.
In bowl, beat egg whites until foamy. Add cream of tartar. Beat until stiff then add sugar and vanilla. Fold in crushed saltine crackers.
Place mixture in a greased 13x9-inch baking pan. Bake for 25 minutes. Cool.
Spread Cherry Pie Filling on top of mixture, then cover with whipped topping. Cover and chill 6 to 24 hours.
Cut and serve.