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Rhubarb blondies on white board with knife. Partially cut with two squares pulled apart
115Total Time
45Prep Time
30Bake Time

Rhubarb and Custard Blondies

Influencer recipe

4 Reviews

  • Nut Free
  • Vegetarian

About the bake

When the flavours of rhubarb and custard sweets meets blondie the results are incredible. Add Janes Patisserie into the mix too and you know you are going to be in for a fabulous bake. 

This recipe from Janes Patisseries recipe book really is next level Rhubarb and Custard cake. You can either bake with fresh rhubarb or tinned, if it is out of season (use the syrup from the tin rather than 2 tbsp of water) so these blondies can be enjoyed all year round. 

Not a fan of Rhubarb? Experiment with different fruits; cherries, blackberries and apples they all taste super scrummy. 

115Total Time
45Prep Time
30Bake Time


  1. Step 1:

    Chop the rhubarb into pieces, and add to a pan with 50g of the sugar and the water. Place over a medium heat, stirring occasionally, for about 5 minutes, or until the rhubarb softens. Set aside to cool.

  2. Step 2:

    Preheat the oven to 180°C/160°C fan and line a 23cm square tin with parchment paper.

  3. Step 3:

    Put the melted unsalted butter and remaining 250g sugar into a large bowl and beat until smooth. Add the eggs and beat until smooth, then add the plain flour and custard powder and beat until combined. Fold through the white chocolate chips or chunks.

  4. Step 4:

    Pour the mixture into the tin and spread out evenly. Dollop the rhubarb mixture and custard over the top and swirl through slightly using a cake skewer or knife.

  5. Step 5:

    Bake the blondies for 30–35 minutes, or until there is an ever so slight wobble in the middle. Leave the blondies to cool fully in the tin before cutting into 16 squares.


  • For the Blondies

    • 175g Rhubarb (fresh or tinned)
    • 2 tbsp Water
    • 200g Unsalted butter (melted)
    • 300g Silver Spoon White Granulated Sugar
    • 3 Large eggs
    • 125g Allinson's Plain White Flour
    • 75g Custard powder
    • 200g White chocolate chips
    • 100g Custard

Nutritional Information

per 74g
  • 302cal Energy
  • 16g Fat
  • 9.3g of which Saturates
  • 37g Carbohydrates
  • 27g of which Sugars
  • 3.6g Protein
  • 0.14g Salt

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