Baby Blue 21st Birthday Cake

I made this baby blue 21st birthday cake for sweet Pei Yie’s 21st birthday. I was quite surprised with her choice of baby blue as the theme color for the cake as typically, young ladies and girls often go with more feminine pinks or purples and the like for their cakes. Baby blue is a very sweet color nevertheless, and I truly enjoyed decorating this cake for her.  

To be frank, this baby blue 21st birthday cake design was not my original design, I tweaked it based on an image provided by my customer. And I traced the design on the internet and found it to be by Michelle from Inspired by Michelle (www.inspiredbymichelle.wordpress.com). Michelle’s original color of the cake was tiffany blue and did not have the 3D key nor the 3D lettering. She however, had a tag with an alphabet “T” on it. Based on my customer’s request, I omitted the tag but added a 3D key to the cake and the birthday girl’s name in 3D letters. Here is Michelle’s original 21st birthday cake as shared by my customer:

21st Birthday Cake


Overall, I must say that my baby blue 21st birthday cake was pretty straight forward to decorate and the only part where it went a bit tricky was with the bead borders for the first tier. Since the cakes were not stacked in an aligned position, upon stacking, I realized that the corners of the top tier ended right at the edges of the bottom tier. That means there was no support for the bead border around these corners of the first tier. Lucky for me, I had my fondant glue to the rescue. I attached with border beads with fondant glue and held them in place for a few minutes until they were secure in place. Let's see how I decorated this baby blue 21st birthday cake below.


Baby Blue 21st Birthday Cake Decorating Guide

This were the main supplies needed for this baby blue 21st birthday cake:

  • Cake – this was a 2 tier square cake with the tiers measuring 8 inches and 10 inches each. The height of each tier was 4 inches. I used my chocolate cake recipe for the cake.
  • Buttercream – I used chocolate buttercream to fill the cake as well as to crumb coat it.
  • Fondant – The entire cake was covered in fondant. I used Satin Ice white , baby blue and black fondant.
  • Gum paste – I used very little gum paste in this project, and that was only for the numbers ‘21’ on the round disc toppers on the cake. And I used Satin Ice gum paste for this purpose.
  • CMC powder – I added this to my fondant when making the circle discs, the 3D key and the bow. CMC helps fondant to set hard and firm, enabling it to hold shape in 3D form.
  • Lollipop sticks – these were used as picks for the circle disc toppers on the cake and held the numbers ‘21’ on them.
  • Key template – this was a handrawn template on a piece of paper. I used this as a guide to cut out the 3D key in fondant.
  • Silver dragees – these were store bought and I used them on the bottom tier, at the edges of each diamond lattice.
  • Round cutter set – I used a medium sized cutter from this cutter set to cut out the circle disc toppers on the cake.
  • Round plunger cutter set – I used the largest cutter in the set to cut out the pastel blue polka dots on the top tier of the cake.
  • Alphabet cutters - I used 2 different cutters for this cake. The first one was FMM Tappit block letters and numbers cutter set . I used this for the numbers ‘21’ on the cake. The other set of cutters I used were also block letters , but these were larger than the FMM font and I used these cutters to make the 3D lettering on the cake as well as the birthday message on the cake board.
  • Pizza cutting wheel – this was a general cutting tool throughout the project, and was particularly useful for cutting the fondant strips of the bow.
  • Airbrush & silver metallic sheen paint – I used airbrush to paint the 3D key and the 3D letters on the cake. The silver sheen airbrush paint was from Americolor.
  • Toothpicks and wooden skewers – I used toothpicks for the 3D letters and 3D key, to help hold them in place on the cake. Similarly, I used wooden skewer to hold the 3D bow in place on the cake.
  • Fondant glue & shortening – these were the ‘glues’ I used to stick my fondant deco on the cake. They were used interchangeably throughout this baby blue 21st birthday cake project. 
Baby Blue 21st Birthday Cake Decorating Guide


And this was how I assembled the baby blue 21st birthday cake:

I started by preparing some of the fondant deco on the cake in advance. These were the bow and the circle fondant toppers on lollipop sticks with the numbers ‘21’ on them. Both these deco were made with fondant that has been added CMC into. CMC helps the fondant set hard and firm and therefore enables the bow and the cut outs to hold shape when put on the cake.

I did not capture the step by step images of making the fondant bow but I do have a tutorial on how to make a similar fondant bow which I made for a baby shower cake. The bow on this cake was made following the same steps except that this bow is wider. Click here to see the fondant bow tutorial.

As for the circle toppers, these were cut using my round cutter set and each circle was about 0.5 cm thick. I made them thick so that I could insert the lollipop sticks into them without tearing the fondant piece. And the numbers 21 on each of these discs were cut out using FMM block letters alphabet cutters. I used gum paste for the letters and air brushed them in silver. I attached them to the discs with shortening only after the air brush paint as set completely.

I also made the 3D key topper and the upright standing 3D letters in advance. These were also made using fondant that has been added CMC. For the key, I drew the key on a piece of paper and used it as a template to cut it out in fondant.  And while it was still soft, I attached a toothpick to its base so that will be easier to hold the key in place once its placed on the cake.  The letters, on the other hand, were cut using alphabet cutters and these were also attached with toothpicks.  Both these deco were made in white fondant and I airbrushed them in silver using Americolor silver sheen airbrush color. 

Closer to the event date, I baked the cake and once it has completely cooled, I leveled the tiers, filled and crumb coated them with buttercream and then covered them with fondant. The bottom tier was covered in baby blue fondant while the top tier was covered in white fondant. 

For the bottom tier, upon covering the cake with fondant, while the fondant was still soft, I used my diamond lattice imprinting tool to imprint the diamond lattice design all around the sides of the cake. And then I attached a silver dragees at the corner of each lattice. To attach these, I used the back of my paint brush to make a slight dent on the fondant, dabbed a little fondant glue into each hole and then pushed one silver dragee into each hole. This way, the dragees will remain in place and not fall off while transporting the cake.

And before stacking the top tier on the bottom tier cake, I added 4 wide strips of white fondant on all 4 sides of the cake and 2 additional strips that were hanging on the sides. All these were attached to the cake with shortening. 

For the top tier, I added similar wide strips of fondant, but this time, it was in baby blue fondant. And again, I added 2 additional strips in the same baby blue color hanging on the front sides of the cake. To make them appear naturally curved, I rolled some kitchen papers and put them underneath the fondant strips and removed them once the fondant has set, leaving the strips looking slightly curved.

Next, before adding the bow, I attached the baby blue polka dots on the cake. These were cut out using my round plunger cutter and I used shortening to attach them to the cake. 

Once these were in place, I attached the fondant bow to the cake. I attached a wooden pick to the bow and applied some fondant glue to the base before putting it onto the cake. The pick is an additional measure to hold the bow in place. And I used fondant glue instead of shortening so that the bow is securely attached to the cake. 

Next to go on the cake was the 3D key followed by the birthday girl’s name. And then the circle disc toppers went on. 

After that, I added the cake borders. I formed the fondant balls by hand and attached them to the cake with fondant glue. I would normally use shortening for cake borders, but because the corners of the first tier cake as at the edges of the second tier, there is not much support for the fondant balls in these sections so I had to use a stronger ‘glue’ so that they are well secured in place.

Next were the birthday lettering on the cake. These were cut using the same cutters I used for the 3D letters that formed the birthday girl’s name on the cake. And I attached these to the cake board with shortening.

And finally, for the finishing touch, since my customer wanted a total of 21 candles on the cake, and since there was not much space on the cake itself to put the candles, I decided to place 20 of them on the cake board in an organised pattern and the remain one candle went on the front of the bottom tier. To hold the candles on the cake board, I cut out round pieces of fondant with a thickness of about 30mm and poke a candle each into the centres. And I attached these ‘candle holders’ to the board using fondant glue. 

And with that, the 21st birthday cake for Pei Yei was complete.


Baby Blue 21st Birthday Cake Decorating Guide

Hope this was helpful.

If you have any questions, please leave them below and I will revert as soon as I can.


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Baby Blue 21st Birthday Cake Decorating Guide


Happy Decorating :) 











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