To make Lemongrass gin: Clean and cut up 3 stalks of lemongrass into 4-inch strips and add to a 750ml bottle of London Dry Gin in an airtight container. Stir and cover. Let sit for 1 hour then refrigerate overnight (8-10 hours). Strain and store in gin bottle in the fridge when not in use.
To make cocktail: Add all Ingredients to a mixing glass filled with ice and stir well. Strain into a chilled coupe and garnish with lemongrass.