The science bit
Under normal circumstances,
water freezes at 0C. But adding salt
to the ice lowers the temperature
to -10C, meaning the milk freezes
Place the milk, sugar and vanilla into
the doubled-up medium zip-seal bags.
Close and secure with sticky tape if the
seal isn’t strong. Tip the ice and salt into
the large bag, then place the smaller
bags inside the larger one, and seal well.
You will need to keep the bags moving
for 10-15 mins to freeze the milk. Gently
throw the bag from hand to hand or
take turns shaking it – it’s a good idea
to wear gloves to keep your hands
warm! Remove the ice-cream bag,
open and scoop into bowls. Sprinkle
with hundreds & thousands.