Preheat oven to 180 degrees C. Grease and line bottom of a 20cm round cake tin.
Place flour, sugar, oil, egg, rind, juice and milk into a bowl and with an electric mixer beat until well combined. Pour into tin.
Cook for approximately 45 minutes or until a skewer comes out clean.
When cake has about 10 minutes left to cook, prepare sauce: place all sauce ingredients into a heatproof bowl over a saucepan of boiling water. Stir until melted and smooth. Transfer sauce to a pouring jug.
Place cooked hot cake onto a serving dish. Tip some of the sauce over the cake. Serve with cream and remaining sauce.