Add the pecans, the sugar, the water and the salt to a skillet.
Cook over medium heat until the sugar has caramelized - stay close by, to make sure it doesn't burn.
When the caramel thickens, turn off the heat, leave it in the skillet, and set it in a cool place to dry.
Add the bananas, and the condensed milk to a blender.
Then use the empty can of condensed milk, and fill it up with the cream, then add that cream to the blender as well.
Blend well until everything is combined and frothy. Like a smoothie.
Add to an ice cream machine to churn. Churn until its starts to firm up like a milk shake, and then add the nuts to be folded in, very slowly.
Keep churning about 10 more minutes.
Pour to a tin pan, or an ice cream container. Freeze overnight.