Preheat the oven to 180°C, fan 160°C, gas mark 4. Grease 2 large baking trays (or line them with baking paper).
Put the butter, both sugars and vanilla extract into a bowl and beat together until soft and creamy. Crack the egg into the bowl and stir to mix together.
Add the flour, bicarbonate of soda, oats, fudge and dried fruits, and mix everything together.
Dollop 18 portions of the mixture onto the trays (as evenly-sized as possible so they cook in the same time). Bake for 10-12 minutes until slightly golden – they should still be soft as they will harden up during cooling.
Leave to cool on the trays and then place on a cooling rack to cool completely.