Cake Soap

cake-soapCake soaps are some of the best examples of creative Melt and Pour soap making. The finished results can be quite stunning and can easily be tailored to different occasions, seasons, or simply made to mimic the real thing in virtually any style. For the purpose of this recipe we have created a classic ‘Christmas cake’ soap, but there will be many other variations you can think of. It really is not that difficult to master these techniques. The main point to always remember is that to avoid colours bleeding into each other, care should be taken to use the correct combination of dyes and pigments.


Equipment you’ll need…

  • Kitchen scales
  • Small-medium saucepan
  • Kitchen knife
  • Gas or Electric hob
  • 20cm silicone circular ‘cake’ mould
  • Hand sprayer
  • Measuring spoons
  • Cutters for decorations. 


  1. Clear Soap base 850g (700g melted for base, 100g as chunks for base layer, 50g for ‘soap glue’)
  2. White Soap Base 700g (200g in base, 250g in ‘marzipan’ layer, 250g in ‘icing’ layer)
  3. Cosmetic Glitter (5g each green & red)
  4. Cocoa powder 3 tsp
  5. Colours: Caramel Powder 5% by weight in water (makes brown liquid dye) 7.5ml and yellow water-dispersible pigment 2.5ml)
  6. Titanium White powder 5g
  7. Soap Fragrance (Christmas Spice) 15ml
  8. Witch hazel (you may use denatured alcohol if you have a license to obtain it) in hand sprayer


Step 1choc_chunks 1
Mix 3 tsp of cocoa powder with a little water to a smooth paste. Melt 200g white soap base and add the paste gradually to the soap base. Stir thoroughly and pour into a suitable container to make a layer aprox 5mm thick. Once set, cut into small chunks as shown.
Step 2chunks in silicone mould 2
Cut 100g of clear soap base into similar-sized small chunks and together with the ‘chocolate’ chunks, scatter into the base of a 20cm round cake mould as shown.
Step 3saucepan with base melt 3
Gently melt 700g of clear soap base over a low heat in a heavy-bottom saucepan. Once melted…
Step 42 bottles frag and colour 4
Add 15ml of ‘Christmas Spice’ fragrance oil and 7.5ml of Caramel Powder in water (brown liquid dye) to the melted soap base. Stir thoroughly and…
Step 5
Pour over the chunks of soap in the base of the cake mould.
Step 6set cake base 6
Spritz with Witch Hazel (or denatured alcohol if you have it available) to clear the surface of any bubbles and leave to one side. Once set but still warm, score the top surface with a sharp knife to aid adhesion of the next layer.
Step 7mixing marzipan 7
Meanwhile… gently melt 250g of white soap base over a low heat. Once completely melted add 1.25ml (1/4 tsp) of Water Dispersible Yellow Pigment (our ref. KD401.70) and stir thoroughly.
Step 8pouring marzipan 8
Pour the yellow soap base (mazipan layer of the cake) into the mould, creating an even layer. This works best by pouring from the outside edge into the centre. Spritz with witchhazel or denatured alcohol to remove bubbles. Leave until set but still warm.
Step 9scoring the marzipan 9
Then… once again, score the surface with a shap knife to aid adhesion of the next layer.
Step 10titanium 10
Mix 2.5g (1/2 tsp) of titanium dioxide white pigment into a paste in a little water. Gently melt 250g of white soap base over a low heat and add the white paste to this, stirring thoroughly to ensure there is no ‘spotting’ of the white pigment. This ‘extra whitening’ improved the appearance of the ‘icing’ layer.
Step 11pouring icing 11
Pour the whitened soap base in another layer into the mould as shown. Once again, this works best if pouring from outside edge into centre.
Step 12undecorated cake 12
Once set but still warm, carefully remove the ‘cake’ from the mould and it’s ready to cut and decorate. In this instance we’re decorating with a seasonal ‘Holly leaf and Berries’. To cut the cake, simply use a sharp knife. It’s helpful but not compulsory to use a guide to get all slices equal. These are available from cake shops, or you can make a paper ‘stencil’. Important. This cake MUST be cut whilst still warm. Cut cake BEFORE decorating.
Step 13glitter_13
Gently melt 50g of clear soap base and stir-in 1 tsp of red cosmetic glitter pigment. Pour into a suitable container to make a thin layer (the inside of a ‘Tupperware’ lid is ideal) of aprox 3-4mm thick. Repeat this process with green cosmetic glitter pigment, but pour into a thinner layer (aprox 1-2mm thick). Once set…
Step 14decorations 14
Cut out your leaves and berries. In this instance we’re using a plastic pastry-cutter for the leaves and the bottom of a small funnel for the berries, but you could easily hand-cut the leaves and use any suitable small round ‘pipe-like’ object for the berries.
Step 15finished-cake
Once you have arranged the decorations to your satisfaction, melt a small amount of clear soap base and ‘glue’ each peice in place with a tiny spot of melted clear soap.

If you’re intending to sell your soaps, make sure you label them with a warning as being SOAP, NOT FOOD, to avoid any problems with the 1989 food imitation act and subsequent EU legislation that has been introduced, which is meant to protect the unsuspecting public from eating something which is not intended for consumption.