Layers of pound cake, toffee ice cream, and pumpkin ice cream stack up to make this fabulous dessert. The foolproof meringue is made with powdered egg whites and marshmallow cream.
Line 8-1/2 x 4-1/2-inch loaf pan with plastic wrap with enough overhang to cover top. In large bowl, whisk pumpkin, sugar and pie spice. Stir in 1 pint softened ice cream. Spoon into prepared pan, smoothing top. Freeze until ice cream is firm enough to put next layer on top, about 1 hour.
In same bowl, stir together remaining ice cream and toffee bits. Spoon over top of pumpkin ice cream layer, smoothing top. Bring sides of plastic wrap over to cover top. Freeze several hours or overnight until firm.
Cut cake horizontally in half. Save one piece for snacking. Place other on ovenproof serving platter or in shallow baking dish.
Heat oven to 500 degrees F.
In large bowl, mix powdered whites and warm water. Let stand 2 minutes; stir to dissolve. Beat at high speed until soft peaks form. Beat in marshmallow until stiff peaks form.
Remove pan from freezer; remove wrapped ice cream from pan. Fold sides of wrap back from top of ice cream; invert ice cream onto cake layer. Peel off wrap. With spatula, spread entire cake and ice cream with egg white mixture, sealing completely to platter and decoratively swirling.
Bake on middle shelf in 500 degree F oven until lightly browned, 3 to 4 minutes. Makes 12 servings.