For the lime syrup (optional)
For the cocktail
If you’re pushed for time you can use shop-bought lime cordial but it really is worth the extra few minutes if you can make your own. To do this, put the grated zest into a saucepan. Squeeze the juice into a measuring jug – stop when you get to about 60ml then top it up with water so you have 100ml of liquid in total. Pour this into your pan with the sugar. Heat very gently, stirring occasionally just until the sugar has dissolved but don’t let it boil. Strain the mixture into a heatproof jug and leave to cool.
To make the gimlet, put a martini or coupe glass in the fridge to chill. Pour 50ml of lime syrup or cordial into a jug or tall glass and add a few ice cubes and the gin. Stir, until the outside of the container feels very cold. Strain the mixture into your chilled glass and garnish with a slice of lime or edible flower.