Set aside 4 cups for serving.
Heat one tbsp of butter and toast the coconut till mildly brown. Allow to cool completely.
Powder the digestive biscuits and mix with the rest of the butter, after melting. Divide equally into the bottom of the cups.
Sprinkle half of the toasted coconut into the cups. Top with the sliced banana.
Layer with caramel on top and then with the whipping cream.
Sprinkle the rest of the coconut as topping on all four cups. Also, sprinkle the pistachio bits if using.
Allow the pudding cups to set in the fridge for a couple of hours. Enjoy!