Sugar and Caramel

As a sugar syrup boils, water evaporates and its temperature climbs, and each stage sets differently when cooled: soft for fudge, firm for toffee, brittle for honeycomb. Caramel is the last stage, when the sugar itself starts to break down and brown, at about 170°C.

That is far hotter than boiling water and it sticks to skin. Use a heavy pan, keep children and pets clear, and have a bowl of cold water nearby.

Stages

Soft ball, 112 to 116°C: fudge and fondant. Firm ball, 118 to 120°C: soft caramels. Hard crack, 149 to 154°C: brittle, honeycomb and toffee apples. A sugar thermometer is the easy way; dropping a little syrup into cold water and feeling how it sets is the old way.

Crystallisation

A syrup can suddenly seize into a grainy mass when a single crystal sets off the rest. Dissolve the sugar fully before it boils, then stop stirring for good; swirl the pan instead.

Brush down any crystals on the sides of the pan with a pastry brush dipped in water. A spoonful of glucose syrup or a squeeze of lemon juice in the syrup helps prevent it.

Wet and dry caramel

Wet caramel starts with the sugar dissolved in a little water. It is slower and more forgiving, so better for a first try.

Dry caramel is sugar melted on its own, swirled as it liquefies at the edges. It is quicker but needs close watching and colours unevenly if left.

When to stop

Take it off the heat at the colour of an old penny or strong tea. It keeps darkening from the pan's heat for some seconds, and moments too long turns it bitter.

Adding cream or butter stops the cooking. Warm the cream first, add it standing back, as it will spit and rise, and stir once the bubbling dies down. Cold cream can make the caramel seize into lumps; these melt again over a low heat.

Washing up

Fill the pan with water and bring it to the boil. The caramel dissolves away, and so does any set on the spoon.