CRUST: Preheat oven to 375 degrees F. Line a 9" springform pan with a circle of parchment paper. Line a cookie sheet or jelly roll pan with parchment.

Cream margarine and sugar in your mixer. Add salt and flour and combine well. Remove a scant 1 cup of the dough and crumble onto prepared sheet pan. Roll out remaining dough to fit the springform and press it in. Bake crust and crumbs for 15 minutes. Remove from oven and cool.

LEMON MOUSSE: Beat egg whites until stiff peaks form. Stir together xylitol and lemon juice until xylitol has dissolved. Add lemon zest, and optional food color. Set aside.

Using a clean bowl and beaters, whip topping until stiff. Fold together whipped topping and egg white mixture. Fold in lemon juice mixture. Pour mousse into the cooled crust and spread evenly with a spatula. Sprinkle baked crumbs on top. Garnish with lemon peel and mint leaves. Freeze 6 hours or longer. Serve semi frozen.

Preheat the oven to 350 degrees.

Cream the margarine and the ¾ cup of xylitol. Add the flour, baking powder, eggs, and salt and beat to mix well. Batter will be soft.

Spoon the batter into an ungreased 9" springform pan. Arrange the plums, skin sides down on the batter. Mix the cinnamon with the remaining xylitol and sprinkle over the top.

Bake for 40 to 50 minutes, until a cake tester inserted in the center comes out clean. Remove from the oven and let cool; refrigerate or freeze if desired.