Don't have crystallized ginger? Mix 1 teaspoon ground ginger with the powdered sugar when making the filling.
A serrated or electric knife will help you cleanly cut the cake into 2 layers. Use these knives for slicing the cake as well.
Save a step or two by just cutting the cake into slices and topping with the filling or topping with frozen (thawed) whipped topping and garnishing with the chopped crystallized ginger.