MMMMM----------------------------TART--------------------------------- 1 9 inch refrigerated ready -pie crust; (1/2 15-ounce ; package), room ; temperature 1 ts All purpose flour; (heaping) 1 1/2 c Pitted fresh cherries or -frozen; thawed and well ; drained 3 tb Grated bittersweet; (not -unsweetened) or ; semisweet chocolate For zabaglione: Whisk yolks and sugar in top of double boiler over simmering water to blend. Gradually whisk in Marsala. Continue whisking until mixture is tripled in volume and holds shape in spoon, about 5 minutes. Set top of double boiler over bowl filled with ice and water and whisk zabaglione until cool. Remove from over water. Beat cream and sour cream in medium bowl to stiff peaks. Whisk in zabaglione. Cover and refrigerate until well chilled. (Can be prepared 1 day ahead.) For tart: Preheat oven to 400F. Dust 1 side of crust with flour. Gently transfer crust to 9-inch tart pan with removable bottom, floured side down. Press into pan and press to seal any cracks. Trim edges. Pierce all over with fork. Bake until golden brown, about 15 minutes. Cool on rack. Drain cherries on paper towels. Arrange in crust. Spoon zabaglione cream over. Cover and refrigerate at least 1 hour. (Can be prepared 3 hours ahead.) Sprinkle with chocolate and serve. Serves 6. Bon Appetit June 1990 NOTES : A sophisticated finale thats easier than pie. If you have a little extra time, you might make your own pastry shell.