Grease and line a 20cm x 20cm (8" x 8") tin and set aside.
Mix together melted butter (115g) and brown sugar (165g).
Add mashed banana (1 large), dates (140g - roughly chopped), egg (1), and vanilla (1½ tsp) and mix to combine.
Add in plain flour (160g) and mix just enough to combine.
Pour batter into greased and lined tin and bake for 25 - 30 minutes until slice is slightly browned at the edges and a skewer comes out cleanly.
Cream Cheese Frosting
In a bowl combine room temperature butter (115g), cream cheese (250g), and vanilla (½ tsp) and mix with a handheld mixer until light and fluffy.
Add icing sugar (360g) and mix until combined and spread on top of cooled base.
Notes
You really need soft ripe bananas (even over-ripe) for this recipe - when they are mashed you are looking for an almost liquid (thick liquid!) consistency not just small chunks of banana. This is because the banana itself provides moisture to the base.
Don't overmix the addition of the flour - just mix enough so there are no streaks of flour in the mix.
I have used dried dates in my recipe, but you could use fresh dates instead if you have them.
The cream cheese frosting is quite soft. If you would like it a bit thicker then just add more icing sugar.
*Please note that the amount of calories per serve is provided as a guide only, as ingredients and cooking methods can vary greatly*