To make the pancakes, sieve the flour, baking powder and salt into a large mixing bowl and make a well in the middle. Whisk the buttermilk and water together. Pour the eggs into the middle of the well, followed by a good splash of the buttermilk mixture.
Gradually start to incorporate the flour into the wet ingredients, by whisking from the middle and working your way outwards until you have a thick but smooth paste. Now start to add the rest of the buttermilk mixture, adding just a little at a time and whisking thoroughly between each addition, until you have a smooth and lump free batter.
Heat a large heavy based frying pan and add a couple of teaspoons of sunflower oil. Wipe the pan with kitchen paper to grease the base of the pan evenly with oil. Pour a small ladle of the batter into the pan for each pancake. Fry for 1 minute until golden brown underneath, then flip over and cook for a further 45 seconds–1 minute on the other side (they should puff up). Continue with the rest of the batter, frying in batches of 2-3. Keep the pancakes warm in a low oven.
For the bananas
For the bananas sprinkle the sugar into a heavy based non-stick pan and melt the sugar over a moderate heat. Once the sugar has completely melted, turn the heat to high and cook to a mid-golden brown.
Stir in the butter then add the bananas and toss to coat in the caramel. Cook for 1-2 minutes until slightly golden and just tender (check with the tip of a palette knife). Now pour in the rum and flambé, tossing the bananas around the pan. Once the flame subsides, add a splash of water, remove from the heat and stir to loosen the mixture.
Serve 2 pancakes per person with the bananas and a scoop of vanilla ice cream on top. Drizzle with the caramel sauce from the pan and serve straight away.