In a saute pan melt 1 tablespoon butter, add sugar and tangerines. Stir continuously 2 minutes; as it cooks sugar will begin to turn golden and thicken. Carefully add Grand Marnier. Note: IT WILL IGNITE. Shake pan until flame goes out, then reduce 1 minute more. Stir in remaining butter and spices. Scoop ice cream into dessert bowls and spoon tangerines on top. Garnish with chopped zest.