Grape Tart

Dough: Sift flour and 2/3 cup sugar into a medium-size mixing bowl. Cut in butter with a fork until the mixture resembles coarse crumbs. Add egg, egg yolk, half the lemon peel and salt; mix to form a soft dough. Cover the dough with plastic wrap and refrigerate for 20 minutes.

Preheat oven to 350°F (175°C).

Roll out chilled dough into a 12-inch circle; place in an ungreased 10-inch springform pan folding the edge down to form a 1-inch high rim (pinch and pat as necessary to create an even edge). Prick crust all over with a fork before baking. Bake crust for 10 minutes; remove from oven and let cool.

Filling: Beat egg whites in a medium mixing bowl until stiff and glossy, gradually adding remaining 1/3 cup sugar and cream of tartar while beating. Fold in almonds and remaining lemon peel until well combined; then fold in grapes halves. Spoon evenly into crust and bake for another 30 minutes at 350°F (175°C).

Remove from oven, let cool for 5 minutes, then remove from pan and cool on a wire rack. Refrigerate, covered with plastic wrap, for an hour before serving.