Preheat oven to 180C/160C fan.
Soak the dates in hot water for 30 minutes, then drain and rinse.
Mix together the oat flour, sugar and salt in a large bowl.Rub the butter into the flour and add in the cold water. Mix until you have a smooth dough.
Press the dough into and up the sides of a 9 inch (23cm) loose base tart tin. Prick the base a few times with a fork and bake for 25 minutes. Leave to cool.
Add the soaked dates to a blender/food processor along with the rest of the date caramel ingredients and blend until smooth***.
To make the whipped coconut cream – refrigerate 2 cans of full fat coconut milk in the fridge overnight (or at least 8 hours), then spoon out the thickened cream only (not the water).
Add the solid cream to a large bowl and beat with a hand mixer until creamy and smooth.
To assemble - spread the date caramel over the base, then top with the banana slices and dollop the cream on top. Finish off with a sprinkle of dark chocolate shavings.