• Preheat the oven to 200C/400F. Grease and line a 20cm/8 inch square baking tin.

For the easy raspberry puree

• Whiz the raspberries in a food processor or with a hand-held stick blender until smooth, then press through a fine mesh sieve over a bowl. Add the sugar to the bowl of thick raspberry juice and stir to combine. Set aside.

For the Pistachio Blondies

• In a large bowl, sift together the flour, baking powder and salt.
• Stir the sugars into the slightly cooled butter then add the beaten eggs and vanilla and mix well. Add the butter mixture, pistachios and chopped white chocolate to the flour mixture and gently combine.
• Pour the batter into the tin and spread to the edges evenly. Add teaspoons of the raspberry puree to the top of the batter (you won’t need it all. Save the remainder to serve) and use a knife to cut through the raspberry to create swirls or hearts. Bake for 20-25 minutes, or until the edges are set and the middle is slightly jiggly but beginning to set.
• Allow the blondies to cool completely in the pan, then cut into squares to serve.
• They’re lovely topped with a scoop of ice cream, raspberry puree and chopped pistachios.