2 tsp liquid smoke (optional, we used Stubb's Hickory Liquid Smoke, available from Waitrose)
1 garlic clove, crushed
Combine the ingredients in a saucepan, then season. Bring to the boil and bubble for 3-4 mins until the sugar and salt have dissolved and the sauce is glossy. Remove from the heat, transfer to a jar, and leave to cool. Will keep in the fridge for up to 2 weeks.