* Prepare orange by cutting off strips of the rind, being careful not to include any of the white pulp just beneath the orange part of the rind. Cut enough rind and cut into small slivers to make 2 tablespoons. Squeeze the orange and strain; measure out 1/2 cup and set aside.

In small pan, combine 1 cup water and 1/2 cup sugar. Bring to a boil over high heat and then stir in orange rind that has been slivered. Lower heat and keep mixture at barely simmering state; simmer uncovered until mixture is like syrup, about 10 minutes or so. Stir in the ginger and set aside to cool to lukewarm. In a large bowl, combine the mashed potatoes, 1/2 cup orange juice, whipping cream, margarine, vanilla and the 3 egg yolks. Beat this until very well combined. Stir in the cooled syrup mixture and beat well. Place 2 egg whites in bowl and beat until soft peaks form. Stir this into potato mixture; do not beat but blend it very well. Pour this mixture into the unbaked pie shell. Make sure you smooth the top of the pie. Bake in a preheated 350-degree oven 45-50 minutes or until knife inserted 1/3 distance from edge comes out clean. The center will be just the slightest bit soft. About 20 minutes before pie is done, prepare the topping.

Topping: Place the 4 remaining egg whites in a large bowl along with the cream of tartar. Beat at low speed until frothy. Increase the speed and Very gradually add the remaining 1/2 cup sugar. Continue beating until whites are very glossy and stiff. This will take about 12-15 minutes. When pie is done, remove from oven and spoon on the egg whites. Don't smooth the top; make soft peaks with the back of a spoon. Continue baking for 10-15 minutes longer at the same 350-degree temperature until meringue is very light brown. Remove to a wire rack to cool.

* This topping will "weep" if kept overnight so plan to serve the same day it is prepared.