1: Bring the water, rum and vanilla pod and seeds to the boil in a saucepan over a high heat. Add the dates, cover the pan, remove it from the heat and leave the dates to soak for 1 hour.
2: After the dates have soaked, preheat the oven to 180°C/Gas Mark 4 and grease and flour six 10cm ceramic ovenproof dishes. Sift the flour and bicarbonate of soda together and leave to one side. Beat the butter and soft dark brown sugar together until light and fluffy. Beat in the eggs, one at a time. Beat in the sifted flour, then fold in the date and rum mix.
3: Pour the batter into the dishes and smooth the surfaces. Place the dishes in the oven and bake the puddings for 12–15 minutes until a skewer stuck in the centre of each comes out clean. Transfer the dishes to a wire rack and leave the puddings to cool for 10 minutes.
4: Meanwhile, to make the decorative toppings, thinly slice the bananas. Fan the slices into six 10cm circles on a metal baking sheet, then dust each with demerara sugar.
5: Use a blowtorch to caramelise the sugar. Remove the puddings from the dishes, then use a fish slice to gently transfer the glazed banana circles to the top of the puddings. Serve with the toffee sauce. If you decide not to serve the puddings while they are still warm, they can be left to cool completely, then wrapped in kitchen foil and stored in an airtight container for 2–3 days.
Put the sugar, butter, golden syrup and treacle in a saucepan over a high heat and bring to the boil, stirring to dissolve the sugar. Continue boiling until the sauce becomes a golden caramel colour. Pour in the cream to stop the cooking.
Add the salt, then pass the sauce through a fine sieve into a bowl and serve warm.
(Leave any leftover sauce to cool completely, then keep in a covered container in the fridge for a couple weeks. Reheat gently to serve.)