Preparation
Melt the butter then grease and line a 15cm loose bottomed cake tin. Preheat the air fryer to 160°C.
Set aside 7 of the raspberries, then tumble the rest into a bowl for juiciness and toss with 1 teaspoon of light brown sugar. Leave to sit while you make the blondie batter.
Beat together the sugars with the melted butter and egg. Combine the plain flour and baking powder and fold into the batter. Chop the chocolate into small chunks and fold 80g into the mixture. Scrape into the tin. Use a fork to mash the sugared raspberries into a chunky purée. Dot teaspoons of the purée over the batter, then use a skewer to gently swirl through the batter. Dot the reserved raspberries over the top, gently pushing in.
Transfer the tin to the air fryer and air fry for 16-18 minutes or until mostly set but with a slight wobble in the middle. Leave to sit on a wire rack and let the tin cool fully. Melt the remaining chocolate in a microwave in blasts then drizzle over the blondies for extra sweetness. Transfer to the fridge and leave to firm up for 2 hours before slicing.
These squidgy raspberry blondies are best kept in the fridge and will keep well in the freezer too in the unlikely event you have any leftovers!