Hello lovelies,
It wouldn’t be an occasion without a cupcake, right? I personally think it would be a god damn crime to allow Halloween to pass by without sharing at least one simple, old fashioned cupcake recipe with a spooky twist.
If you want cupcake that is guaranteed to catch someone’s eye and is utterly delicious, your in the right place as these monster slime cupcakes I’m sharing today will get top remarks from all those who take a bite. That’s a dead cert.
I’ve taken inspiration today from the incredibly talented Kat, also known as ‘The Baking Explorer’ online. She posted her version of these cupcakes online back in October a few years ago and I’ve had them saved in my bank of ‘bakes to do’ for a hot minute.
So, i thought it was about damn time that I got making them and let’s just say, these cupcakes didn’t disappoint. They were everything I’d hoped they’d be and more.
{ Kat’s Original Recipe: https://thebakingexplorer.com/slime-cupcakes/ }
If these cupcakes have caught your eye and your wanting to make them yourself this Halloween, you know the drill. Continue scrolling below and you’ll find the recipe!

Category: Sweet Treat
Servings: 12
Prep Time: 10 Minutes
Cook Time: 20-25 Minutes
Decorating Time: 15 Minutes
Overall Time: 1 Hour
Ingredients You Need For Cupcakes:
- 200g Of Butter / Stork
- 200g Of Caster Sugar
- 4 Large Eggs
- 150g Of Self-Raising Flour
- 50g Of Cocoa Powder
- 2tsp Of Vanilla Extract
Ingredients You Need For Decorating:
- 2 x 150g Pots Of Ready-To-Eat Custard
- 150g Of Unsalted Butter, Softened
- 300g Of Icing Sugar
- 2tsp Of Vanilla Extract
- Lime Green Food Colouring
- Edible Eye Decorations
How To Make The Cupcakes:
- Firstly, gather together your equipment and ingredients, line a 12 hole muffin tin with 12 Halloween cupcake cases and preheat the oven to 180C / 160C Fan / Gas Mark 4.
- Secondly, in a large bowl, using an electric whisk, beat together the 200g of butter with 200g of caster sugar until light and fluffy.
- One at a time, beating well between each addition, add in the 4 medium eggs.
- Next, beat in the 150g of self-raising flour and 50g of cocoa powder until just combined.
- Evenly divide the chocolate cake mixture between the 12 cupcake cases.
- Place the muffin tin into the oven and bake for 20-25 minutes, until a skewer placed into the centre comes out clean.
- Once baked, remove from the oven and allow to cool to room temperature.
How To Decorate The Cupcakes:
- Now that the cupcakes have cooled, using a cupcake corer or knife, core out the centre of each cupcake (TIP: don’t core the complete centre of the cupcake, stop just before you reach the bottom).
- In a small bowl, add the 2 x 150g of ready-to-eat custard and 3-4 drops of lime food colouring and mix together until the custard has turned completely green.
- Spoon the green coloured custard into the centre of the cupcakes. Then, place a small piece of the cored cupcake on top of the custard to keep it secured.
- Next, in a large bowl, using an electric whisk, beat the 150g of softened unsalted butter for 2-3 minutes, until loosened and smooth.
- In small batches, beat in the 300g of icing sugar and 2tsp of vanilla extract until a silky smooth buttercream has formed.
- Add 2tsp of lime green food colouring to the buttercream and mix in until the buttercream has turned a vibrant green.
- Place the buttercream into a piping bag which has been fitted with a Wilton 4D piping nozzle (or any star shaped nozzle you’ve got).
- Pipe the buttercream onto the cupcakes.
- Finally, carefully place the edible eye decorations all over the buttercream.
That’s your Monster Slime Cupcakes prepared, baked and decorated, ready for you to enjoy this Halloween.







And that’s a wrap for Halloween 2023 here on the blog!
I may have only got around to posting three Halloween bakes this year but I’ve got to say, they are three of my absolute favourites to date. I feel like the vibe for this year was simple yet effective, do you agree?
We certainly ended with a bang! I know for a fact these cupcakes will be a firm favourite with the little ones, the slime centre just makes these cupcakes all that more exciting. Kat absolutely smashed it with these bad boys!
Let me know in the comments below if you make these cupcakes yourself and if you do, what your thoughts are on them. The outcome is just brilliant, right?
Sending you all tons of love & hugs as always,
Elle xo