Butter a 4-cup heatproof pudding basin generously and have a large saucepan half-filled with simmering water and a trivet or an upturned saucer in the base of it.
Beat together the sugar and eggs until pale and fluffy, add the melted butter and beat again, then add the apricot jam.
Sift on the flour, baking powder, salt and fold through, followed by the baking soda, dissolved in the milk. Stir to combine.
Place the golden syrup in the bottom of the pudding basin, then pour the mixture into the basin and cover with a double layer of baking paper or tin foil.
Tie the cover on with string and lower carefully into the simmering water. Steam for 1½ hours. Check the water level occasionally and top up with boiling water. Turn out and serve with cream and Edmonds custard.