Unicorn Slime Cake Project

Level: Advanced


  • 1 x 6" ½ ball cake tin
  • 1 x 6" round 'Mondo' cake tin or giant cupcake tin
  • 3 x portions of moreish buttercake - see below recipe
  • 2 x tubs of white 'Over the Top' buttercream
  • 2 x tub of blue 'Over the Top' buttercream
  • 1 tub of princess pink glitter edible slime
  • 1 set of round 'Mondo' cookie cutters
  • 1 x 10" round white 'Mondo' cake board
  • Your Choice of Gel Food Colour
  • 1 tub of white 'Fondtastic' gumpaste
  • 1 tub of white 'Fondtastic' fondant
  • A sharp knife
  • 'Mondo' dasiy plunger cutters
  • 'Mondo' butterfly plunger cutters
  • 'Over the Top' sprinkles in unicorn or mermaid mix and silver balls
  • 1 small 'Mondo' rolling pin
  • 1 x bamboo skewer (for the horn)
  • 1 packet of 'Mondo' plastic pipping bags
  • 1 star or swirl 'Mondo' pipping tip
  • 1 container of gold or any colour petal dust with a little alcohol or Lemon essence Glue



Step 1 - Take 100 grams of White Fondtastic Gum paste and roll it into a ball and then into a log shape. Take your time with making the horn and follow the steps as it will help you create a nice shape. Keep rolling unto the middle is thick, and both ends are tapered to a point- this might take 2 goes to get it right. Once you have the correct shape, gently bend in half so that the 2 pointy ends are evenly.

Now twist from the bottom - it is easier if you twist one end over the other each time - trying not to just twist one side all around the one side as it won't come out evenly. Keep on twisting, one side over the other, until you have twisted it all the way to the end.

Next cut off the end at the height you want the Unicorn horn to be. A word of advice, too short and it looks stumpy, too long as it's not proportioned to the cake, we suggest leaving it a little longer than you think it will be as you can always cut extra off later. Dipping the end of a bamboo skewer into a little bit of Over The Top Edible Sugar Glue and gently insert it approximately ½ way into the Unicorn horn - this will help you keep the horn in place on the cake, especially if it needs to be transported after it's finished. Leave the horn aside to dry for a couple of hours.


Step 2 - Roll out a little more of the gum paste, using the thickest guides on your Mondo small rolling pin. Use a tear drop cutter, (often referred to as a petal cutter) cut out 2 of the second smallest cutters for the outside of the ears and set aside. Re-roll the gum paste, this time with the thinnest bands on your rolling pin and punch out 2 of the smallest tear drop cutters for the inside of the ears. Then use a little bit of edible gold paint to paint the 2 smaller tear drops in gold.

Again use a little Over The Top Edible Sugar Glue to secure the gold small tear drop on top of the larger tear drop, just leaving it a little space so that you can see the white part of the ear as shown. Trim a little bit off the end of the ears (approx ½ a centimeter) and discard the part you trimmed off. Curve the ears gently at the bottom so they can sit up right, leave them sitting upright and curved to dry for a couple of hours.

To create the eyes of the unicorn roll out a little more white Gum paste, using the thickest rolling guides on your Mondo rolling pin. Use the 5cm and 6cm round Mondo Cookie Cutters on the smooth side and punch out 2 x 6cm round circles.

Then use the 5cm round cutter and position it along the edge of the circle so you are trimming approximately a ½ centimeter in the middle and the 2 side are tapered down to pointy end. Repeat this with the other circle in the same way so you end up with 2 equal moon crescent shapes.

You won't need what is left over of the circles, so those and be kneaded back up and put away for another use later. Shape your crescents a little along the ends to create a nice curved shape for the eyes. Paint the eyes in gold paint, or the colour you want and leave aside to dry.


Step 3 - For the decorations take some Fondtastic Gumpaste and colour it slightly with different colours from the Chefmaster Gel Food Colour range. We used soft pink to yellow to Leaf Green. Then use the various plunge cutters from the Mondo range, we used butterflies, daisies and blossoms to cut out a good selection of shapes, once cut leave to dry. Bend the butterfly's wings slightly upwards to give them a super cute effect! You can do the same with the flowers and bend the petals up a little. You can then decorate them more by adding edible beads and sprinkles from the Over The Top Sprinkles range by Mondo and use a little bit of edible glue to secure them in place. Leave everything to dry while you work on the cake.


Step 4 - Next up, bake the bottom of your giant cupcake, this can be in a purpose tin or a 6" round Mondo baking tin, leave a side to completely cool before doing the next steps.

You can use the recipe provided below. It's a good idea is to bake both the bottom section and the 6" ½ ball cake at the same time. Then using a sharp serrated bread knife, slice off the top dome of the bottom section so that it's even.

Handy tip - If you do this when the cake has been chilled in the fridge for a few hours it help reduce the crumbling of the cake as you cut it.

Using the 8cm round Mondo Cookie Cutter on the smooth side, press it into the cake in the middle of the bottom section. This will give you a perfect round and depth of the cavity you will need to fill with Edible Pink Princess Slime. If you edge the cookie cutter out on one side it will pull the cake out with it, leaving a perfect hollowed centre for you. Next up is the top section of the giant cupcake cake - this is the 6" ½ ball cake tin - bake a portion of the cake mix (preferable at the same time you baked the bottom bit!) and like the bottom section, use a sharp knife to trim off any cake that has risen during baking.

Handy tip - Once the cake is cooled, reline the tin with cling wrap and put the cake back inside, it'll help conserve the shape as you do the next step!

Following the same process you did with the bottom section, do the same to the ½ ball and edge out a section of it. Using a little Pale Pink Over The Top Buttercream, crumb coat both cavities - this will help seal in the slime and ensure the cake doesn't absorb the slime later.

Handy tip - You can either use Pale Pink Buttercream straight from the tub or mix a little Soft Pink Chefmaster Fold Gel into the Over The Top Buttercream, the choice is yours.



Step 5 - Next up, fill both cavities with Over The Top Edible Pink Princess Slime to the top.


Step 6 - Buttercream the base and a bit of the top cake as you are about to flip the top ½ ball section on top of the bottom. Place the top ½ ball section on top of the bottom and crumb coat using buttercream over the entire cake. Place a little Buttercream in the middle of a 10" round white Mondo cake board cake board and secure the cake to it. Pop it into the fridge to firm up for 10 to 15 minutes.


Step 7 - Next, roll out a sheet of Fondtastic White Fondant and cover the entire cake, smoothing the surface as you go.

The top isn't as important to smooth as you will be covering it in Buttercream later, but the bottom is. To create the effect of a cupcake wrapper on the bottom of the cake, I used the Mondo Balling Tool. First I ran a small ball down the base to give me the indentation and the spacing. And I then used the largest ball to make the indents wider and more pronounced. I then ran the rolling tool around the division of the top of the "cupcake" and the "cupcake wrapper" as it helps me later work out where to cover with Buttercream.

Placing a Mondo Star Piping Tip into a Mondo Plastic Pipping Bag, load the bag with plain White Over The Top Buttercream. Start piping rosettes around the top section of the cupcake. To pipe a rosette, start in the middle and swirl around it to the outside, its only 1 swirl around the middle to achieve the look.

Keep you going until it's all covered and looks cute!


Step 7 - Now the fun part really starts! With the horn, paint it gold using edible paint. And place the horn in the dead center of the dome, the bamboo skewer will help keep it in place.

If the horn is too long, you can trim around the bottom with a sharp knife and insert. Position the ears by placing them just slightly forward of the horn and turned in slightly, the Buttercream will help secure them in place. Next, with a little edible sugar glue, position the eyes in place, if you position them in line with the ears it will help keep the look proportioned. Optional - you can add a little pink petal dust to a new cotton bud and created a blush effect on the cheeks.


Step 8 - It's your choice here if you prefer to use colour straight from the tubs, or mix in gel colours into the White Over The Top Buttercream. Lay out a sheet of cling wrap and lay down a thick layer of pink Buttercream - I love pastels.

You can also use the Chefmaster Gel Colour range to colour the White Buttercream and mix them separately, approximately 75 to 100 grams of each was done for the next process:

  • Leaf Green
  • Soft Pink
  • Violet
  • Yellow
  • Sky Blue

Keep on adding a line of each colour or the colours of your choice so that it looks like a rainbow. Gently roll it all up into a giant pretty rainbow sausage of Buttercream goodness! Twist the ends to firmly secure it together. Trim off the cling wrap on one end only with a sharp pair of scissors (this should be trimmed so that the Buttercream is exposed). Using the Mondo Star Piping tip, place it into a Mondo Plastic Piping bag and The

then slip the rainbow Buttercream sausage into the bag, with the exposed Buttercream section in head first.

Start by piping on some pretty swirls around the horn and in front of the ears. Then trickle down to a "V" shape on the front of the unicorn to just above the eyes. Then, using all the pretty gum paste flowers, butterflies and sprinkles decorate as you like!



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