How to Make a Number 5 Birthday Cake

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Step-by-step instructions for making a number 5 birthday cake. Photos included.

If you need a number 5 cake for your next celebration, here are some step-by-step instructions on how to make it yourself. Creating a number cake is fun and festive and places an emphasis on the special day, whether its for a birthday or anniversary.

First, you have to bake a large sheet cake. Wilton carries an 11in x 15in sheet cake pan that is perfect for the job. Follow the instructions on the cake pan when preparing your batter. I always use boxed cake mix with wonderful results. Don’t forget to buy cake boards that are slightly larger than your cake pan, they come in handy when decorating and transporting your cake. Cake boards are available at craft supply stores, such as Michaels.

Next, you want to apply a layer of thinned butter cream icing, to Crumb Coat your cake. Once the icing is crusted over, you can use the tip of a sharp knife to outline the number you want to make. You can also use a wooden skewer for this job or to help make straight lines. If you mess up, just touch up the frosting and start over.

Now comes the fun part…cutting the shape of your number cake. It is a little nerve-racking, but the only way to go about doing it, is to just do it! Remember that it is only cake, take a deep breath, grab a sharp, serrated knife, and get to cutting. Start at the easy edges, and work your way toward the center. If you are unsure, be conservative, because you can always trim more later when you start to see the shape emerge. With the number 5 cake, there are only 3 cuts, but go slowly with the two larger cuts, since they curve. You can touch it up once you have most of the cake out.

Don’t worry if your shape is a little rough around the edges. That’s what icing is for! Use buttercream icing in the color of your choice to frost the cake smooth. Use your angled spatula to help create sharp edges and smooth your icing. Use a decorating bag with a tip of your choice to create a border that will hide any imperfections.

Now that you have your number 5 cake cut out and frosted, get creative and come up with a design that will transform this number cake into a special number 5 birthday cake or 5th year anniversary cake. If your celebration is in the double digits, make two number cakes to suit the occasion.

In the finished version of this number 5 birthday cake, I kept the design simple and left the icing smooth and white, with an orange shell border, using a number 21 tip. I also used a cookie cutter and Wilton’s pre-made Ready-to-Use Rolled Fondant to make the flowers, which were similar to the flowers on the birthday invitation for this party.

Now you know where to begin, when you want to make a homemade birthday cake for your child’s next party or number cake for any other special event.  It's that simple!

Important Tips to Remember:

  • Wait until your cake is completely cool before you start cutting
  • Water down your icing before applying the first Crumb Coat, this layer is just to seal in the cake so it doesn’t get all crumby when you’re applying the final frosting.
  • Before cutting your outline, it helps to stand on a chair to get a bird's eye view, just to make sure it looks right.
  • If your cake is uneven, use icing to create a level surface, by building up the icing in the low spots
  • When your cake is complete, DO NOT point out all the imperfections to your guests!
  • Have fun and be creative!


James R. Coffey
Posted on Apr 25, 2011
Posted on Apr 10, 2011
Sandy James
Posted on Apr 10, 2011