Slice the bananas and lightly steam or pan-grill them with butter until caramelized.
Melt 2 tablespoons of butter in a saucepan.
Add 2 tablespoons of palm sugar, stirring until it dissolves completely into the melted butter.
Add 3/4 cup of water to the mixture and bring it to a boil.
Stir in 1/3 cup of coconut milk and mix well.
Once the mixture has thickened slightly, stir in the cornstarch slurry and let it thicken further for another minute or two.
Add a pinch of salt and remove from heat. Drizzle this caramel sauce over the prepared bananas.