Heat the oven to 180C/Fan 160C/ Gas 4. Lightly grease four mini pudding basins. Thin the Tangy Orange Curd with 1 tbsp lemon juice and divide between the basins.
Put the basins in a roasting tin. Put the kettle on to boil.
Cream the butter and caster sugar together with the lemon zest and diced stem ginger until fluffy then gradually beat in the egg, followed by the flour and baking powder. Add the lemon juice, plus 2 tbsp warm water to give a pourable batter.
Divide between the basins, then pour boiling water into the roasting tin to come halfway up the basins. Cover the tin with a tent of foil and bake for 20-25 minutes until risen and cooked through. Leave to settle for 5 minutes, then turn out and serve with custard.