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Raspberry & Custard Blondies Recipe
Ash Tyrrell

Raspberry & Custard Blondies Recipe

I stumbled onto this recipe on a lazy weekend when I had a handful of raspberries going soft in the fridge and a craving for something gooey. I whisked up a simple brown sugar batter, swirled in a quick homemade custard, and scattered raspberries across the top before baking
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Prep Time 20 minutes
Cook Time 30 minutes
Ingredients Method Notes

Ingredients
  

  • 200 ml whole milk – forms the base of your custard layer so use full-fat for the richest texture
  • 3 tablespoons instant custard powder – gives that nostalgic thick custard without any fuss
  • 115 g unsalted butter – melt it until nutty and golden for deeper flavor in the batter
  • 220 g light brown sugar – keeps the blondies fudgy and adds a caramel-like sweetness
  • 1 large egg – binds everything together and helps create that classic chewy blondie texture
  • Zest of 1 lemon – brightens the whole bake and balances the sweetness beautifully
  • 125 g plain flour – the backbone of the batter spoon and level it so you don't overpack the cup
  • ¼ teaspoon fine salt – rounds out the flavors so nothing tastes flat
  • 150 g fresh raspberries – go for fresh not frozen, so they don't turn the batter watery

Method
 

  1. Preheat your oven to 180°C (350°F) and line your square baking tin with baking paper, letting a little hang over the edges. This makes it so much easier to lift the finished blondies out later. Set the tin aside while you get started on the custard and batter.
  2. In a saucepan, whisk together the milk and custard powder over medium-low heat. Keep whisking constantly so no lumps form as it thickens. Once it's thick enough to coat the back of a spoon, pour it into a bowl and let it cool while you work on the batter.
  3. Using the same saucepan, melt the butter over low heat until it foams and turns a light golden color with a nutty aroma. This step adds serious depth of flavor to the final blondies. Once it stops foaming, take it off the heat and let it cool slightly.
  4. In a mixing bowl, whisk the brown sugar, egg, and lemon zest together until the mixture turns pale and slightly fluffy. Pour in the cooled melted butter and stir until fully combined. This forms the sweet, buttery foundation of your blondie.
  5. Sprinkle in the flour and salt, then stir just until you no longer see streaks of flour. Overmixing at this stage can make the blondies tough, so stop as soon as it looks combined. The batter should be thick and slightly sticky.
  6. Spread most of the batter into your prepared tin, saving a few spoonfuls for the top. Pour the cooled custard evenly over the batter, then scatter the raspberries across the surface. Dot the reserved batter randomly over the top so some custard peeks through.
  7. Bake for 25 to 30 minutes, until the top turns golden but the center still looks slightly soft. Because of the custard layer, a skewer won't come out clean, so trust the color and gentle wobble instead. Let the tray cool completely before slicing.

Notes

  • I always let my butter cool for a few minutes before adding it to the sugar mixture, or the egg starts to cook and turns rubbery.
  • I use room-temperature eggs since they blend into the batter far more smoothly than cold ones.
  • I pat my raspberries dry with a paper towel before adding them, which keeps the batter from turning soggy.
  • I chill the blondies fully before slicing, since warm custard makes for a messy cut.
  • I line my tin with paper on all sides, not just the bottom, because it makes lifting the whole slab out so much simpler.