Cupcakes: Heat oven to 350*F. Mix together dry ingredients, set aside. Mix hot water and cocoa until dissolved, set aside. Beat shortening and sugar for 30 seconds. Add sugar, beat another 2 minutes. Add eggs, vanilla, and orange peel. On low speed, alternately add flour mixture and cocoa (1/3 of flour, 1/2 of cocoa, etc.) Pour into cupcake tray/cups, and cook for 20-25 minutes. Icing: Mix butter and chocolate. Stir in powdered sugar. Beat in vanilla and 2 tablespoons orange juice. Add remaining oranges juice one teaspoon at a time until reaching desired consistency. Topping: Cut orange slice in half, then each half into 6 pieces. Top each cupcake with three pieces.