In a separate bowl (not a plastic bowl) beat 1 egg white until stiff and fold into milk and orange juice mixture. Pour filling into chocolate crust.

To prepare meringue: Beat the remaining 3 egg whites and cream of tartar until eggs barely hold a peak. Gradually beat in sugar 2 tablespoons at a time until mixture is stiff and forms peaks. Swirl meringue over pie filling making sure to seal filling with meringue. Bake in the oven for about 10 minutes or until meringue is golden brown.