Put the blueberries, caster sugar and lemon in a cocktail shaker and mash with the end of a rolling pin. Add the black pepper, gin, Limoncello and some ice and shake well. Put a large ice cube into each glass along with 3 blueberries and pour the cocktail in through a sieve. Top up with soda water.
Recipe by appetite magazine at https://www.appetitemag.co.uk/gin-and-blueberry-twist/