Cut pound cake on diagonal into eight 1/2-inch-thick slices. Using 3 1/4-inch-diameter cookie cutter, cut out 1 round from each slice; top each with 1 scoop ice cream.
Transfer to baking sheet. Freeze until firm, about 1 hour.
Beat egg whites and cream of tartar in large bowl until soft peaks form. Gradually add sugar; beat until stiff peaks form, about 4 minutes.
Transfer 1 cake-ice cream piece to work surface.
Spread 1 scant cup meringue over, swirling to make peaks and covering completely. Return to sheet in freezer. Repeat with remaining cake-ice cream pieces and meringue. Freeze until firm, about 3 hours. (Can be made 1 day ahead. Keep frozen.)
Preheat oven to 450°F.
Bake until meringue is light golden, about 5 minutes.
