Steamed syrup sponge pudding
Generously butter the inside of a 1.2 litre/2 pint pudding basin, and cut a circle about two times larger than the pudding basin diameter, of baking paper and kitchen foil.
Spoon 50g/2oz of the golden syrup into the base of the pudding basin and set aside.
Beat the remaining 50g/2oz golden syrup, butter, sugar and lemon zest with an electric whisk until light and fluffy. Whisk in half of the eggs followed by half of the flour. Whisk in the remaining beaten eggs and flour. The mixture should be a just dropping consistency. (Add a splash of milk if the mixture is very thick.)
Spoon the mixture into the pudding basin and smooth the surface.
Pleat the baking paper by folding over an inch of paper in the centre. Repeat with the foil. This allows for expansion of the pudding as it cooks.
Cover the basin with the circle of baking paper, with the pleat in the centre of the pudding. Cover the paper with the circle of kitchen foil, again with the pleat in the centre. Tie the pudding very tightly around the rim with string. Create a carrying handle by tying the excess string across the top of the basin and tying it under the string on the opposite side – this will help you lift the pudding out of the pan once it’s cooked. Trim any excess paper and foil, leaving a 2.5cm/1in border, and turn the edges in on themselves to seal.
Put an upturned heatproof saucer or small trivet in a large, deep saucepan, and place the pudding basin on top. Add enough just-boiled water to the pan to come halfway up the sides of the basin. Cover the pan with a tight-fitting lid and place over a low heat. Allow to steam in the gently simmering water for 1¾ hours, adding more water to the pan if necessary. (Make sure the pan does not boil dry.)
The pudding is done when a skewer inserted into the centre of the pudding (through the kitchen foil and baking paper) comes out clean. When done, turn off the heat and carefully lift the basin from the water. Leave to stand for 5 minutes.
Cut the string from the basin and discard the kitchen foil and paper. Run a knife around the edge of the pudding to loosen the sides, carefully turn out onto a deep plate and remove the basin.
To serve, spoon the extra syrup over the pudding, cut into generous wedges and serve with custard.
Be really careful not to let the pan boil dry, but avoid removing the lid of the pan during the first 20 minutes of cooking time if you can, as this can create a flat, heavy sponge.