Martha's mocha swirl blondies

Martha's mocha swirl blondies

Gooey blondies with a delicious chocolate and coffee swirl.

4 out of 5 stars(1) Rate this recipe
  • Makes16
  • CourseDessert
  • Prepare30 mins
  • Cook30 mins
  • Total time1 hr
  • Plusplus cooling

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  • 150g butter
  • 150g light brown soft sugar
  • 100g caster sugar
  • 75g white chocolate, broken into cubes
  • 2 British Blacktail Medium Free Range Eggs
  • 200g plain flour
  • ½ tsp baking powder
  • 2 tsp espresso powder
  • 2 tbsp cocoa powder
  • Sprinkling of cacao nibs


  1. Preheat the oven to 180ºC, gas mark 4. Grease and line a 20x20cm square tin with baking parchment. In a large saucepan, heat the butter, light brown sugar and caster sugar together until the mixture has completely melted. Remove from the heat and allow to cool for 5 minutes, then add the chunks of white chocolate. Stir until melted, then allow the mixture to cool to room temperature – if you don’t allow it to cool, the eggs will scramble when you add them.

  2. Beat the eggs into the cooled mixture using a wooden spoon. Sieve over the flour and baking powder and mix until well combined. Dissolve 2 tsp coffee powder in 1 tsp of boiling water, then stir this paste into the batter.

  3. Spoon three-quarters of the mixture into the prepared tin and use a spatula to spread it out evenly. Add the cocoa powder to the remaining mixture and mix well. Use a teaspoon to dollop this chocolate mixture randomly over the coffee mixture, then use a skewer to swirl the mixtures together. Sprinkle over the cacao nibs.

  4. Bake the blondies for 25-30 minutes, or until risen with a slight wobble in the centre. Leave in the tin to cool completely, preferably overnight (if you can resist!) for them to become fudgy and dense before slicing. These blondies will keep for 1-2 weeks in an airtight container.

Cook’s tip

Martha’s tip

The best blondies have the right amount of squidge in the middle. Get them out of the oven when there is still a slight jiggle in the centre – they will continue to cook as they cool, leaving you with soft, squidgy blondies instead of cakey ones.


Typical values per item when made using specific products in recipe


1,028kJ/ 246kcals



Saturated Fat












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4 out of 5 stars1 rating