In a medium bowl, whisk to combine the cream, almond milk, salt and granulated sugar until it's fully dissolved. Stir in the vanilla. Cover and refrigerate for 2-3 hours or overnight.

In a medium skillet or saucepan, toast walnuts over medium-low heat. Transfer to a small bowl.

Using the same skillet, melt the butter. Add the brown sugar and stir until it's dissolved and begins to bubble. Add the bananas and cook about 2 minutes, until softened. Carefully stir in the rum and cinnamon, and cook for another 2 minutes. Remove from heat and allow to cool. Transfer to a bowl, cover and refrigerate until you're ready to make the ice cream.

When the ice cream is almost fully churned, gradually spoon in the banana mixture, followed by the walnuts. Let go for a minute or so (do not over mix).

The ice cream will have a soft and creamy texture. If you prefer hard ice cream, transfer it to an airtight container and place in the freezer for about 2 hours. Remove about 10 minutes before serving.