1. Fill a bowl with warm water, add a pinch of salt and stir to dissolve. Add the banana skins and leave to soak for a minimum of 30 minutes and up to 6 hours. Drain the banana skins and cut into thin strips.

2. Heat the vegetable oil in a large saucepan or deep frying pan, add the curry leaves and cumin seeds and fry over a medium heat for about 20 seconds. Then add the onions, garlic, ginger and coriander stalks and cook for about 5–8 minutes until the onions are softened.

3. Add the banana skin slices and cook for another 8 minutes.

4. Stir in the spices and cook for 1 minute, then add the peanut butter, breaking up any clumps with the back of the spoon. Pour in the coconut milk, measured water and lime juice, add the sugar and stir to combine. Bring to asimmer, then reduce the heat and cook gently for about 30 minutes until the sauce has thickened.

5. Thin with extra water if it becomes too thick. Season with salt to taste.

6. Serve scattered with the coriander leaves.

FOR PEANUT BUTTER AUBERGINE CURRY

Swap the banana peels for 4 aubergines, cut into 4 cm (11/2 inch) chunks. Sprinkle with a little salt and leave for a couple of minutes, then pat dry with kitchen paper. First, heat 4 tablespoons vegetable oil in the pan, add the aubergine in batches and fry for about 6–8 minutes until browned. Drain on a plate lined with kitchen paper and set aside while you cook the sauce base in the pan as above. Once you have added the coconut milk, water, lime juice and sugar, stir in the fried aubergines and continue as above.

Minimise food waste with this antioxidant-rich peanut butter and banana peel curry