1. Add the sultanas, raisins and rum to a bowl and set aside for at least 2 hours or until the line of liquid visible in the bowl has reduced, and the dried fruit is looking plump.

2. Line a slice and brownie tin (about 27cm x 17cm x 3.5cm) with cling film.

3. Remove the ice-cream from the freezer and let it get to a malleable consistency. Scoop out into a serving bowl and add the rum and fruit mixture. Working quickly, stir to incorporate thoroughly. Turn into the lined baking tray, and using the back of your spoon, spread out across the base. Pop in the freezer while you prepare the rest of the elements.

4. For the rum ball mixture, blitz the biscuits in a food processor or blender to a coarse crumb. Turn out into a bowl and add the remaining ingredients. Stir with a wooden spoon until the ingredients are thoroughly incorporated.

5. Remove the ice-cream from the freezer, it will still be soft, and using a dessert spoon, dollop over the rum ball mixture. Don't worry about where it ends up, dollop here there and everywhere – it's part of the ice-cream sandwich lottery. Similarly, dollop over spoonfuls of the dulce de leche. Cover with cling film and return to the freezer to set overnight.

6. You can cut the ice-cream with a 7.5cm round cookie cutter (or the size that best suits your chosen waffles) when ready to serve, or you can do this prior to serving and simply lie the ice-cream discs on a sheet of baking paper in your freezer and have them all ready to go.

7. To assemble, lay one waffle half on a flat surface and top with the disc of rum ice-cream. Top with the other half of the waffle and press down gently to secure. Repeat with remaining waffles and ice-cream discs. Serve immediately.

Note: After adding all the alcohol and mix-ins, this ice-cream does tend to be a little softer. It makes it a lot easier to cut with a cookie cutter mould but it will melt more quickly when placed in warm hands. Ditto the rum ball mixture – this is not intended to be firm enough to roll into rum balls, rather it adds a lovely chewy, soft biscuity textural goodness to your ice-cream sandwich.