1 1/2 quarts nonfat or low-fat vanilla ice cream or frozen yogurt, softened
1/4 cup brandy
1/4 cup coarsely ground gingersnaps
1 1/2 teaspoons minced crystallized ginger
2 large egg whites
1/4 teaspoon cream of tartar
3 tablespoons sugar
1 3/4 cups coarse gingersnap crumbs (about 6 oz.)
2 tablespoons minced crystallized ginger
To make crust:
With a mixer, beat egg whites and cream of tartar on high speed until foamy. Add sugar a third at a time, beating about 45 seconds after each addition, until soft peaks form. Gently fold cookies and ginger into whites. Drop small spoonfuls of cookie mixture over bottom and sides of a buttered and floured 9-inch pie pan. With a spoon, gently pat crust to evenly cover bottom and sides of pan up to top of rim. Bake in a 350*F oven until lightly browned and dry to touch, about 20 minutes. With a metal spatula, loosen cookie crust from sides of pan, then slide spatula under crust a little at a time to completely loosen bottom. On a rack, let cool completely in pan, then place in freezer until cold (at least 10 minutes). Fill crust, or freeze airtight up to 2 weeks.
Make filling and finish pie:
Place ice cream in a bowl and stir in brandy. Spoon ice cream evenly into crust and swirl top. Combine gingersnaps and ginger and sprinkle on top of pie. Freeze pie, uncovered, until firm to touch, 2 to 2 1/2 hours. If making ahead, wrap airtight and freeze up to 1 week.