Preheat the oven to 180°C/fan 160°C/gas mark 4. Grease and line a 20x20 cm baking tin with greaseproof paper.
Place the oats in a large bowl, then roughly chop the dates. Roughly chop one of the bananas. Add the dates and bananas to the oats with the date nectar, melted butter and cinnamon and mix until it just comes together. Press into the lined baking tin and smooth the surface. Slice the remaining banana into ½cm thick slices and arrange 16 slices over the surface. Bake for 35-40 minutes, until golden all over. Leave to cool, then brush with the honey.