Ingredient

Fudge

Fudge is the one sweet where you deliberately want sugar to crystallise — but into crystals so small the tongue cannot feel them. The entire method is about controlling when crystallisation starts, and that is why the instruction not to stir is not optional.

Why you must not stir

While the syrup is boiling, any stirring throws sugar crystals from the pan sides back into the mixture, and each one seeds a large crystal. Large crystals are what "grainy" means.

When you take it off the heat, the syrup is supersaturated — it holds more sugar than it should be able to. If you stir it now, while it is still hot, crystals form fast and grow big. If you let it cool undisturbed to around 43°C and only then beat it hard, thousands of tiny crystals form at once and none of them gets large. That is fudge.

So: no stirring during the boil, no stirring during the cool, then vigorous beating at the right moment. Getting that order wrong is the single commonest reason home-made fudge is grainy.

The sugar stages

A thermometer is genuinely useful here, unlike with caramel.

Soft ball, 112–116°C

Where fudge is made. A drop in cold water forms a soft, squashable ball.

Firm ball, 118–121°C

Firmer fudge, caramels.

Hard ball, 121–130°C

Nougat, marshmallow.

Hard crack, 149–154°C

Toffee and brittle. Snaps rather than bends.

Above 160°C

Caramelisation. A different preparation entirely.

The method

1. Combine sugar, butter and milk or condensed milk in a heavy, deep pan. Deep matters — it rises alarmingly.
2. Stir over a low heat until the sugar has completely dissolved, before it boils. This is the only stirring allowed.
3. Brush the pan sides down with a wet brush, then bring to the boil and stop stirring entirely.
4. Boil to 114–116°C. It takes longer than you expect and then arrives suddenly.
5. Take it off the heat and add any vanilla. Do not stir. Leave it completely alone until it drops to about 43°C — lukewarm to the finger.
6. Now beat it hard with a wooden spoon until it thickens, loses its gloss and turns opaque and paler. Your arm will know when.
7. Pour into a lined tin immediately, before it sets in the pan, and leave it to firm up before cutting.

What goes wrong

• Grainy — stirred while hot, or a stray crystal seeded it. The commonest fault.
• Never set — not boiled to a high enough temperature. Re-boil it with a splash of milk and take it further.
• Rock hard — boiled too far. Melt it down with a little milk and re-boil to a lower temperature.
• Greasy, with butter separating — the mixture split, usually from too fierce a boil. Beat in a spoonful of hot water.
• Set in the pan before pouring — beaten too long, or started too cool. Work faster.

Common questions