Heat the oven to 180C/fan 160C/gas 4 and line a 900g loaf tin with a long strip of baking paper. Keep aside 2 tbsp of the chopped dates for decoration. Tip the rest into a pan, pour over the milk and bring to a boil. Remove from the heat, add the vanilla extract and bicarbonate of soda, then leave to cool.
Meanwhile, beat the butter and sugar with electric beaters until pale and fluffy. Add the eggs one at a time, ensuring each is fully incorporated before adding the next. Mix in the plain flour, baking powder and ground ginger. Tip in the dates with their cooking liquid and mix well. Stir in the stem ginger.
Pour into the loaf tin and bake in the oven for 50 minutes or until a skewer pushed into the centre comes out clean. Remove the cake from the oven to cool completely.
Once cooled, remove the loaf from its tin and onto a serving plate. To make the icing, mix the icing sugar with the ginger syrup and a splash of water, and pour generously over the cake. Top with extra chopped dates and chopped stem ginger to finish.