Filling: 3 large Granny Smith apples, peeled, halved, cored 1 cup sugar 1/3 cup sour cream 3 large egg yolks 1/4 cup all purpose flour 1 teaspoon vanilla extract 1/2 teaspoon cinnamon 1/4 cup raisins Whipped cream or creme fraiche Position rack in center of oven and then preheat to 375 ° F. Butter 9-inch tart pan with 1-1/2-inch-high sides and removable bottom. Set aside. For crust: Using food processor with steel knife. Process flour, butter, sour cream, 1 tablespoon sugar, hard-boiled egg yolk, cinnamon, nutmeg and salt until mixture resembles coarse meal, about 20 seconds. Transfer all but 1/2 cup of mixture to prepared pan. Press mixture evenly into bottom and up sides of pan. Bake 10 minutes. Brush with egg white. Continue baking until brown, about 15 minutes. Transfer to rack. Reduce oven temperature to 350° F. Add remaining 2 tablespoons sugar to mixture in work bowl and process until combined, about 3 seconds. Chill crumb mixture until ready to use. For filling: Insert Medium Slicer. Place apple halves vertically in feed tube. Slice using medium pressure. Transfer to medium bowl. Insert Steel Knife: Process sugar, sour cream, egg yolks, flour, vanilla and cinnamon until smooth, about 20 seconds, stopping machine once to scrape down sides of work bowl. Arrange half of apple slices, overlapping slightly, in concentric circle in prepared crust. Sprinkle half of raisins over. Repeat procedure with remaining apple slices and raisins. Spoon custard over apples, lifting apples slightly and smoothing custard between slices. Sprinkle reserved crumb mixture over top. Place pan on cookie sheet. Bake until custard is set, covering edges of crust with foil if browning too quickly, about 65 minutes. Let stand 10 minutes. (Can he prepared 1 day ahead. Cool completely. Cover and refrigerate. Reheat in 300°F oven about 15 minutes.) Remove sides of pan. Serve warm or at room temperature with whipped cream or creme fraiche. Makes 8 servings. dess 49