Princeton cocktail

Method

1. 1 Mix the gin and Angostura Bitters in a measuring jug and add the ice cubes.
2. 2 Stir well and leave to stand for 5 minutes. Strain into a chilled cocktail glass.
3. 3 Hold the glass at a slight angle and pour the port in a slow steady stream down the side of the glass.
4. 4 Allow it to settle at the bottom for a few seconds.
5. 5 Make the garnish. Pick a few leaves from a rosemary sprig and push them into the top of a raspberry so they look like leaves.
6. 6 Thread the berry onto a cocktail stick and balance on top of the glass, to serve.