Chocolate syrup

Makes 500 ml (17 fl oz/2 cups)

330 g (11¾ oz/1½ cups) caster (superfine) sugar

100 g (3½ oz/½ cup) brown sugar

55 g (2 oz/½ cup) good-quality unsweetened cocoa powder

a pinch of fine sea salt

20 g (¾ oz) good-quality dark chocolate, chopped

½ teaspoon pure vanilla extract

¼ teaspoon cream of tartar

Place the sugars, cocoa powder and salt in a saucepan. Gradually whisk in 375 ml (13 fl oz/1½ cups) water until smooth, then stir over medium heat until the sugar has dissolved.

Bring to the boil and keep at a boil, stirring occasionally with a metal spoon for about 10 minutes, or until the mixture thickens very slightly. It will still be fairly thin, but will thicken again on cooling.

Remove from the heat, add the chocolate and vanilla and whisk until the chocolate has completely melted. Whisk in the cream of tartar until dissolved.

Pour into a sterilised 500 ml (17 fl oz/2 cup) glass bottle or jar and seal while still hot. Cool to room temperature, then refrigerate.

Store in the fridge and use within 6 months; discard if any mould appears, or if the aroma or flavour suddenly changes. Use in chocolate milkshakes, and for topping ice cream and other desserts.

tartar tales Cream of tartar stops sugar crystallising in syrups and confectionery, and also helps stabilise egg whites.