Whip double cream with sweetened condensed milk, espresso, and coffee and vanilla extract just until soft peaks form. Don't over beat, we are not looking for whipped cream here.
Fold in chopped Daim bars with a spatula.
Scrape into a freezer-safe container and cover with a lid or foil. Freeze overnight or at least for 7 hours.
Prior to assembling ice cream sandwiches place biscuits in the freezer to firm up.
To make sandwiches scoop 1/4 cup of ice-cream onto a previously frozen digestive biscuit, top with another one and smooth the sides with a spoon. Repeat with the remaining biscuits and ice-cream.