Instructions

1. Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced. Line a baking tray with baking or parchment paper.
2. Start by making your funfetti cookie crumbs. In a large mixing bowl, add flour, sugar and cornflour. Whisk together. Pour over melted butter, along with the vanilla, stir briefly. Add sprinkles and then stir until cookie crumbs are completely coated and resemble wet sand.
3. Pour crumbs onto a baking tray lined with baking or parchment paper and spread out into one layer. Bake for 10 minutes, then leave to cool completely. 
4. Next, take your leftover cake and roughly crumble it using your hands. Place cake pieces in a large mixing bowl. Stir together milk and vanilla.
5. Add milk, just 1 tablespoon at a time, and gently mix until cake is soft and moist. Try not add too much milk as you don’t want the cake too wet. You may not use all the milk – this is ok.
6. Scoop out balls of cake, approximately 1.5 tablespoons each, and roll them smooth using your hands. Place cake truffles in the fridge for 15 minutes or so until they’re a little more firm.
7. Meanwhile, add white chocolate to a heatproof bowl. Heat in the microwave, stirring every 30 seconds, until melted and smooth. Add oil and stir until smooth.
8. Coat cake truffles, one at a time, in melted white chocolate and then immediately dunk in cookie crumbs. Roll truffles around until they’re completely covered in crumbs. Repeat with remaining truffles.
9. Place truffles in the fridge for at least 1 hour to firm up. Store truffles in an airtight container in the fridge.