Preheat the oven to 150°C/300°F/gas mark 2. Use a convection rather than a fan oven, if possible.

Melt the butter, sugar and syrup over a low heat, stirring until no grains of sugar remain. Keep cooking until the toffee is bubbling and smooth.

Add the oats and stir over the heat for five minutes. Mix in the salt and turn off the heat.

Press firmly into a 10 x 8in tin, lined with non-stick baking parchment.

Bake for thirty minutes, or until deeply golden at the edges.

Dip a wooden spoon in cold water and press the flapjack down firmly.

Leave them to cool for minimum of four hours.

Tip out on to a board, remove the paper and cut into as many pieces as you desire.