Custard Cream Blondies made with white chocolate and stuffed full of biscuits and custard powder. There’s gooey, crunchy deliciousness in every single mouthful.
Your favourite traybake just got the most amazing makeover, you’re going to need these in your life!
I have had so many people comment that they’d love a Custard Cream Blondie recipe and your wish is my command.
I love an easy traybake and all of my blondies use my tried and tested base blondie recipe because it works SO WELL. Custard Cream Blondies only take around 15 minutes to prep they are so easy to make and everything can be mixed in one bowl.
Basic Blondie recipe
You can use this base recipe and add any flavours, or biscuits you like. This recipe will never fail you and will produce ooey, gooey, stick to the roof of your mouth blondies every single time. Because you want them to stick to your mouth and teeth – am I right?!
I put a couple of tablespoons of custard powder into the blondie batter and folded through lots of bashed up Custard Creams because I wanted to make sure the blondies really took on the custard flavour.
I love that the blondies turned a marbled yellow colour. They looked so inviting once they’d been cut up into squares.
If you fancy more of a challenge you might be asking how do you make your own custard creams from scratch?
Well, I have a really easy Custard Cream recipe for you to try. If you have a little time on your hands, it’s so worth making your own because they melt in your mouth and are absolutely delish!
What you need to make the most amazing blondies
White Chocolate – most if not all blondie recipes will include white chocolate. You can use an expensive white choc but I don’t feel it’s necessary. I use cheap white cooking chocolate from Tesco in all my blondie recipes and I can promise you they taste amazing!
Unsalted Butter – salted butter would be too much in these blondies. You can add a pinch of salt to the batter if you want to.
Caster Sugar – lots of recipes call for brown sugar to give a more caramelised flavour. I go with caster sugar when biscuits are star of the bake but you can use any sugar and the recipe will work fine.
Eggs – 3 medium or 2 large free-range eggs.
Vanilla Extract – use extract or vanilla bean paste but not essense.
Plain Flour – any plain flour or all-purpose flour will do, don’t worry about sifting.
Custard Powder – for an extra custard-y hit! I used Bird’s custard powder which is readily available in supermarkets in the UK. For readers in the US, Bird’s is available to buy on Amazon or you may find it in European stores. Or you could always make your own custard powder.
Custard Creams – I folded bashed up Custard Creams through the blondie batter and topped with Custard Creams, you will need some whole, some broken and some crumbs.
AMY’S TIP: Read the advice below on how to make the best ever blondies. This method has been tried and tested many times and is completely failsafe!
- Melting the butter and chocolate (as opposed to creaming it) gives the blondies the best texture.
- Allow the melted butter and chocolate to cool for 5 minutes before adding the eggs, otherwise, they might scramble!
- When it’s time to add the flour, fold it gently with a spatula or wooden spoon. Do not overmix the blondies or will become hard and lose their gooey texture.
- The baking time sweet spot is at 25 minutes, any longer and you risk dry, overbaked blondies.
- Blondies should look squidgy in the middle. If you’re not into that, increase the baking time to 30 minutes.
I hope you love this Custard Cream Blondies recipe. If you have any blondie requests just let me know!
More Tempting Traybakes
If you make this recipe, I’d love to know how it went. Feel free to post a pic on my Facebook Page or tag me @amytreasureblog so I can share your wonderful creations on social media!
I would really appreciate it if you could rate the recipe below and leave me a comment. Thank you so much x
Custard Cream Blondies
- 150 g white chocolate chopped
- 125 g unsalted butter
- 150 g caster sugar
- 3 medium eggs or two large
- 1 tsp vanilla bean paste or use vanilla extract
- 2 tbsp custard powder I used Birds
- 200 g plain flour
- 150 g Custard Creams broken into pieces
- 50 g Custard Creams Whole, broken and crushed – for topping
- Preheat the oven to 170ºC / 150ºC Fan / Gas 3 / 330º F. Line a 20cm (7") square baking tin with baking paper.
- Put the white chocolate and butter into a heatproof bowl and set it over a pan of simmering water. Don't let the bowl touch the water. Stir the white chocolate and butter together until it has melted. Remove the bowl from the heat add the sugar and mix well.
- Add the eggs and whisk thoroughly in an exaggerated motion so that you beat lots of air into the mixture.
- Add the vanilla bean paste and custard powder and whisk until thoroughly combined.
- Using a spatula or wooden spoon, gently fold in the flour until you can no longer see white streaks of flour.
- Tip in the broken Custard Creams and gently fold into the blondie batter.
- Transfer the blondie batter to the sqaure baking tin. Smooth the top with a spatula and press the remaining Custard Creams into the top of the batter.
- Bake in the centre of the preheated oven for 25 minutes. A skewer inserted into the centre will not come out clean. Test the blondies for doneness by shaking the tin – if they wobble a lot then they need a couple more minutes. Once baked, remove from the oven and leave to completely cool in the tin before turning out and cutting into 12 squares.
- After 25 minutes give the baking tin a shake, if there’s still a wobble increase the cooking time in 1-minute increments until the blondies don’t wobble when shaken
- If you want your blondies less gooey in the middle wait until an inserted skewer comes out clean (note: your blondies will become overcooked on top the longer you leave them in the oven)
- Leave the blondies to completely cool in the tray before you attempt to cut them
- The blondies will look very squidgy in the middle (unless you increased cooking time as stated above) this does not mean they aren’t safe to eat and it’s how blondies should look
- Storage: Custard Cream Blondies will keep for 5 days in an airtight container.