Preheat oven to 350 degrees.
Purée three bananas with a hand mixer. Scoop into a big bowl and add all other loaf ingredients. Mix thoroughly.
Pour batter into greased pan. Cut the fourth banana lengthwise in half and place the slices on top. Bake for 45 minutes.
For topping, scoop only the top layer of cream from the can of coconut milk into a bowl. Add honey and vanilla powder and mix until smooth. Serve with the banana nut loaf.
* You can substitute 1.5 teaspoons vanilla extract for vanilla powder.
** The night before baking, put the coconut milk in the fridge (to separate the fluid from the cream).