Preheat oven to 350° (180°C). Line a 10×14-inch (25×35-cm) baking pan with foil and grease lightly. 

In a large mixing bowl, beat egg whites until frothy, using the whip attachment. Slowly add the sugar, continuing to whip until a glossy meringue has formed and mixture is stiff.

Add remaining ingredients except for the pie filling to bowl while the mixer is off. Mix on low speed until blended.

Pour approximately two thirds of batter into prepared pan. Gently combine pie filling with remaining batter, folding until incorporated. Pour over batter in pan and marbleize with a knife.

Bake for 1 hour and 20 minutes, or until toothpick inserted in center comes out clean. Remove from oven and cool completely.

For the frosting: Beat parve whipping cream until stiff. On low speed, slowly beat in pie filling, just until fully incorporated, or mix it in just until marbleized. Frost cake using a swirling motion, to achieve pretty effect. Keep refrigerated until ready to serve.