OK. Not strictly speaking ice creams, but with some frozen fruit always in the freezer, a sudden request for ‘ice cream’ can be met easily and effortlessly. These have worked well in my house:
Frozen watermelon slices
About as easy as it gets. Slice segments of watermelon and freeze them. Allow to defrost slightly before eating. Warning, these can get messy!
Take 10 frozen raspberries and gently smash into small pieces. Pour over 4 level tablespoons of double cream and a dusting of icing sugar and mix well. The cream will harden on contact with the raspberries, giving the texture of ice cream. Serves 1.
Mango and coconut cream
In a high-speed blender blitz 50g of frozen mango pieces with four heaped tablespoons of coconut cream (the thick top layer of @bionaorganiccoconut milk works really well). You could add a little icing sugar to this as well if needed. Serves 1.