Slice the onion and garlic.
Wash the bananas well. Slice the top and bottom of the bananas, remove the peels and scrape the white parts off the inside with a knife. Cut the peels thinly into 2 to 3-inch long shreds.
Transfer them to a bowl and add the olive oil, paprika, chilli, mustard, soya sauce, garlic, onion and cumin. Mix well and set aside to marinate.
Heat a pan over a medium heat and add the marinated banana peel mixture. Add a small splash of water to help the banana peels steam and tenderise. The cooking time will depend on how ripe your bananas are (the riper are they are the faster they cook) so start tasting after a couple of minutes. It’s important that they are tender enough to bite through but not so overcooked that they turn to mush. They should be done in around 5 to 10 minutes. Add another splash of water and keep cooking if the pan goes dry before they are tender.
Add the tomato ketchup and give them another 30 seconds to a minute more to incorporate the flavour. Add a pinch of salt to taste. Remove from the heat and let cool for a minute.
Place the banana peels on your bun and top with coleslaw. Ready to serve!