Preheat the oven to 180°C, fan 160°C, gas 4. Line two baking trays with baking parchment.
Put the soft butter, sugar and vanilla extract into a bowl and beat together until soft and creamy. Crack the egg into the bowl and mix well. Add the flour, baking powder, dried mango and cranberries and mix everything together.
Spoon approx 16 dollops on to the trays and bake for 10-12 mins until just slightly golden – they will still be soft. Leave to cool on the trays and then put onto a cooling rack.
For the fruit pick ’n’ mix, peel and slice the mango down either side of the stone, cut into strips and put into a bowl. Add the berries and mix together. Put into a separate plastic container and take along with the cookies.