Custard Cream Blondies

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Indulge yourself with these Custard Cream blondies! Super easy to make, topped with everyone’s favourite biscuit and packed with white chocolate chunks, they have a beautiful vanilla butterscotch flavour. And with that perfect brownie centre, these are the best ever blondies you’ll ever taste.

Custard Cream blondie slices on a marble board

Do you want to know a secret?

Sssh, don’t tell anyone but when it comes to brownies, I’m more of a blondie girl at heart.

Don’t get me wrong, I love a rich and decadent brownie. I mean just look at these Jaffa Cake brownies or my favourite Rolo ones; how could you not love them? They are utterly delicious!

But when it comes to deciding between blondies and brownies, the blondie wins hands down.

Whether Party Ring blondies chocked full of biscuit pieces and mini marshmallows, or a fruity version with raspberries and blueberries, it’s that perfect butterscotch flavour that gets me everytime!

A hand holding a slice of blondie

What are Custard Creams?

If you’ve never had Custard Cream biscuits before then I urge you to go out and find one.

First made in 1908, the Custard Cream sandwiches a custard buttercream between two vanilla shortcake biscuits, that are distinctive decorated with a baroque pattern.

And with the UK getting through 420,000 tonnes of biscuits a year, the Custard Cream is still one of our best loved biscuits; fending off competition from as newer biscuits such as Lotus Biscoff.

You’re going to love these blondies because…

Apart from the fact they are packed full of biscuit pieces and white chocolate, these really are the best blondies ever! Just take a look at them…

  • Perfectly thick with the ultimate soft and fudgy centre
  • Smooth butterscotch flavour with a hint of vanilla custard
  • Super easy to make in one bowl with no fancy ingredients
  • Easily adapted recipe – use your favourite biscuits in stead
Stack of blondies with biscuit pieces and white chocolate chunks

What you’ll need to make Custard Cream blondies

View my Amazon shopping list with equipment and ingredients.

So now I’ve convinced you that you’ll love these blondies, it’s time to make them. So here’s what you’ll need…

The Ingredients

There’s nothing fancy here, so pop these on your shopping list and get ready to bake:

  • Custard Cream Biscuits – If you can’t find Custard Creams you can use Golden Oreos instead
  • Custard Powder – For a little extra custard flavour in your blondies
  • Caster Sugar
  • Light Muscovado Sugar – The light brown sugar will give the blondies a perfect butterscotch flavour. If you want a richer butterscotch and darker blondie, then switch for a dark Muscovado or brown sugar
  • Plain Flour
  • White Chocolate – You can use either white chocolate chips, or chop a bar of white chocolate into shards
  • Butter – I use slightly salted, but if you want to use unsalted butter add a pinch of fine sea salt.
  • Eggs
  • Vanilla Extract

The Equipment

I absolutely love the simplicity of this recipe especially the minimal washing up that it makes.

If you prefer you can make this with a stand mixer but I make my blondies by hand and use one mixing bowl and a balloon whisk.

You’ll also something to bake the blondies in. A brownie pan is best; either an 8×8 inch square tin or a 10×7 rectangle tin.

Slices of blondie topped with golden biscuits

How to make Custard Cream blondies

Full measurements and instructions can be found on the printable recipe card

I’ve already said how deliciously easy and quick to make these blondies are; so here’s how you make them…

Make the Batter

To get going, sieve the flour and custard powder into a large mixing bowl. Add the sugars and stir everything together.

Melt the butter, then pour over the dry ingredients and whisk together until you have a thick caramel mixture.

Next add the eggs, one by one, whisking well between each egg. The mixture will become smooth and runny. Add in the chopped white chocolate and Custard Cream pieces, and fold together.

Assemble the Blondies

Line a brownie pan with baking parchment, making sure to leave a little hanging over the sides – it makes it easier to lift out later.

Pour the blondie batter into the pan, level off with an angled palette knife, then place the remaining Custard Cream biscuits on top. Push the biscuits into the batter, so they don’t pop out when the blondies bake.

Step by step live video

How to bake the perfect blondie

For both blondies and brownies, the baking time is crucial to getting the perfect bake – the soft, slightly gooey but still holding together centre.

You’ll notice that lots of recipe have different times. The longer the time, the more cakey and dried your blondie will be; now enough time and it will be too liquid in the centre.

I recommend testing the blondies 5 minutes before the recipe bake time is up; and if you need a bit longer get in 5 minute blocks.

Test the edge of the blondies with a toothpick and if they come out with a few crumbs and a smear of batter on, then they’re done!

TOP TIP: Remember the blondies will continue to bake as they cool down, so don’t be tempted to keep baking until the skewer comes out of the centre clean.

Stack of blondies with biscuit pieces and white chocolate chunks

Frequently asked questions

How size brownie pan do I need?

This recipe is best made in either an 8×8 inch square tin or a 10×7 rectangle tin.

How should the blondies be stored?

Once the brownies are cooled and sliced, keep them in an air-tight container at room tempature.

How long will the blondies keep for?

The blondies will keep fresh for up to 3-5 days.

Can I freeze the blondies?

Yes you can. Slice the blondies before freezing and wrap in baking paper and place in an air-tight, freezer-proof container. They will keep for up to 1 month. Remember to defrost thoroughly before eating.

Custard Cream Blondies - Featured Image

Top tips for the best blondies ever

  • Use a mix of brown and white sugar – To get that a perfect butterscotch flavour, use a mix of soft brown sugar and white caster sugar. It gives the blondies that delicious caramel taste. I go with a 2:3 ratio of brown sugar to white.
  • Whisk your ingredients together – Just like a cake, whisking the eggs helps incorporate air into the batter, giving a light bake. The same is true for blondies. Use a balloon whisk to combine everything together and whisk when you add the eggs. This prevents your blondies becoming dense and heavy.
  • The Toothpick Test – You want the blondies to still be soft in the middle so test 1-inch in from the pan edge with a toothpick. If it comes out with a few crumbs and a smear of batter, they’re done. If they are still wet, bake for another 5 minutes and test again.
  • Don’t be tempted to overbake – Overbaked blondies will dry out and have a more cake like texture. You will find different recipes have different bake times, but everyone’s oven is a little different. To get the right bake time, test your brownies using the Toothpick test about 5 minutes before the end of the bake time and bake for a little longer if needed.
  • Let the blondies fully cool – It’s so tempting to go straight in when they come out of the oven, but be patient and let the blondies cool properly. I leave mine in the pan for about 10-15 minutes, then lift out to fully cool on a wire rack. Make sure they are cooled before slicing up.
Custard Cream Blondies - Pinterest Image

More blondie and brownie recipes to try

If you liked these Custard Cream blondies here are some other recipes that I think you’d enjoy…

Custard Cream Blondies - Featured Image

Custard Cream Blondies

5 from 2 votes
Serves : 12 slices
Indulge with Custard Cream blondies! Easy to make, full of biscuit pieces and white chocolate. They're the best blondies you'll ever taste.
Prep Time 15 minutes
Cook Time 30 minutes
Total Time 45 minutes




  • Preheat the oven to 180C/350F, and line a brownie tin with baking parchment.
  • Melt the butter in a saucepan over a low heat or in a microwave in 30 second blasts. Allow to cool for 5 minutes.
  • In a large mixing bowl, add the caster sugar, soft brown sugar and custard powder Mix together, then pour over the melted butter and mix together with a balloon whisk until well combined. The mixture should not be grainy, and the sugar should have dissolved into the melted butter.
  • Add the eggs one at a time and whisk between adding each one. Whisk until the mixture is smooth and thick. Add the vanilla extract and stir through.
  • Sieve the flour into the mixture and gently fold together with a spatula until all combined.
  • Chop the Custard Cream biscuits into chunks, then add into the mixture. Save 12 biscuits to decorate the top of the blondie.
  • Add the chopped white chocolate then fold everything together.
  • Pour the batter into the lined brownie tin, and level with an offset spatula or the back of a spoon. Place the remaining Custard Creams on top of the blondie batter, pushing them down slightly.
  • Bake for 30 minutes, until firm but still a soft in the centre. Leave the blondies to to cool and firm up for above 15 minutes before taking out of the brownie tin. Allow the blondies to completely cool before slicing.


Serving: 1sliceCalories: 469kcalCarbohydrates: 63gProtein: 5gFat: 22gSaturated Fat: 12gCholesterol: 92mgSodium: 221mgPotassium: 128mgFiber: 1gSugar: 39gVitamin A: 487IUCalcium: 61mgIron: 2mg


The nutritional information provided is approximate and is calculated using online tools. Information can vary depending on various factors, but we have endeavoured to be as accurate as possible.

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Hi I’m Lou

… Dessert obsessed baker, busy 9-to-5er, and the recipe developer and photographer behind Crumbs and Corkscrews. Based in the UK, I live in the beautiful Cotswolds. I’m so glad to have you here with me and I can’t wait for you to start trying some of my recipes.

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