1. Wash, peel and dice the rhubarb finely and set aside. Wash the raspberries and dry them.

2. Add the butter and sugars to a large bowl and mix until light and fluffy. Add the egg and vanilla extract and mix in well. Mix the flour with baking soda, baking powder, and salt and then add to the mixing bowl and mix until just combined. Add the diced rhubarb and the raspberries and gently fold in – the more you crush the raspberries, the softer the dough gets, so work gently and quickly. Place in the fridge for about 1 hour.

3. Preheat the oven to 180°C (350°F). Line a baking sheet with baking parchment and set aside. Use a cookie scoop or two tablespoons and place portions of dough with enough space in between on the baking sheet (about 6-8 cookies max.) – the cookies spread a lot. Bake them for about 12-15 minutes. Take the cookies out of the oven and let them cool down a bit on the baking sheet, then transfer them to a wire rack and let them cool down completely. Repeat with the remaining dough. Because of the berries you should store the cookies in a cool place.