Grease 23 cm long rectangular baking dish with butter. Preheat oven to 180°C. If not using a steam oven, place a tray of water on the bottom shelf of the oven.
Place milk and treacle in TM bowl and heat 3 min/70°C/speed soft.
Beat 10 sec/speed 8, pour out and set aside to cool slightly.
Cream the butter and sugar until light and fluffy 2 min/speed 5.
Add all remaining cake ingredients except flour, including treacle milk mixture. Beat 20 sec/speed 8.
Add flour and mix until just combined 22 sec/Interval.
Pour batter into prepared dish and bake or steam bake 30-40 minute until springing back when you push the edge with your finger.
To make the glaze, combine sugar and lemon juice in a bowl and stir with a fork. Drizzle over warm cake.