Crack coconut and drain coconut water into a container. Set aside. Remove all coconut meat from the coconut and place into a bowl. Choose the softest coconut meat, and blend on high speed for about 30 seconds. Gradually add coconut water to reach desired cream consistency. Mix bananas until well blended.
Place crust mixture onto a sheet of wax paper. Pack the mixture with a spatula into a flat circular shape. Add another piece of wax paper to the top, and roll to flatten with a rolling pin, creating a uniform thickness. Place bottom of spring-form pan on top of crust and measure to fit. Position crust on top of pan base and form crust around the base with your fingers. Coat spring-form pan with coconut oil and place the bottom back into the pan. Add banana cream mixture on top of the crust. Add sliced bananas to the top of the pie; place in freezer for one hour prior to serving. Add fresh berries as a garnish.