Using a pastry bag with a large star tip will help you re-create the look of this Double-Layer White Chocolate Cake. Tint each row of frosting a darker shade to produce an ombre effect.

An easy technique that gives your cake a sophisticated look is piping your frosting through a pastry bag. There are different types of bag tips that will get you different looks on your cake:

Round tips are used to make lines, dots, and writing.
Star tips are used to create stars, shells, flowers, decorative borders, and rosettes.
Leaf tips are used to make leaf shapes.
Basket-weave tips are used to make lattices and ribbonlike lines and borders.

How to Decorate a Cake with Frosting

Fill a pastry bag about two-thirds full of frosting.
Fold the corners over, and roll the bag down to the frosting.
With one hand, grip the bag near the roll above the frosting.
Apply pressure with the palm of your hand, forcing the frosting toward the tip.
Use your other hand to guide the tip of the bag.

You can use one of those piping nozzles:

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Try the recipe for our Double-Layer White Chocolate Cake

Easy Cake Decorating Ideas: Add Piping