Here's a quick one. It's been hot in London lately. Really really hot. And this simple cocktail is a great way to cool off after a sweaty day.
First make a simple syrup by combining 1 cup of lemon juice, 1 cup of sugar, half a cup of water and a sprig of rosemary in a pan over a low heat. Bring it just to the boil then turn off the heat and leave to cool and infuse. When cooled, discard the rosemary spring and decant into a bottle or jug.
In a cocktail shaker, shake one part syrup with one part vodka with lots and lots of ice. Shake it really well. Pour into a low ball glass filled with ice. Top up with spritz of soda water or lemonade if you want to make it a longer drink. Decorate with small sprig of rosemary and a slice of lemon.