I did this Princess Castle Birthday Cake for a friend of mine that needed a cake for her grand daughter. I had done a smaller version for another friend but I decided to make it bigger and better this time around. I just used a simple boxed cake for the cake with a simple butter cream frosting in the middle of the two layers. I covered the whole thing in marshmallow fondant which I made myself from a whole package of mini marshmallows, clear butter flavor and clear vanilla extract (melt the marshmallows in the microwave and add a teaspoon of each flavoring. After that simply add in a whole mess of powdered sugar until it is hard and no longer sticky.)
The four towers in the corners I made from cupcakes and the tops of cake cones. I covered the cupcakes in fondant and the cones just frosting. I had to cut a section out of the towers so they would fit onto the main cake. The two towers and spires on top were made the same but with sugar cones instead covered in fondant.
After all that was done I just did a lot of piping work for the details and use some leftover fondant to make the gateway and path.
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This cake is great looking. The towers look so good! The small details are amazing, such as the brick pattern on the fondant walls. This truly is one of the coolest princess castle birthday cakes!