Make slits in the skin of the plantain. Remove the thick green skin. Wash it with running water. Make sure the shape of the plantain remains intact.
Make thin slices of banana using a mandoline slicer or chips slicer. You can do the same using a knife but ensure all pieces are thin and of equal size.
In a large and wide bowl, add water, salt, and turmeric powder. Stir to combine. Soak banana slices in this water for 5 minutes. This step helps remove the starch and give chips a salted flavour.
Drain all the water. Arrange banana slices in a clean kitchen towel. Gently pat them dry. Moist or wet slices won't turn crisp properly while frying.
Brush the air fryer basket with coconut oil. You can use vegetable or refined oil also instead of coconut oil. Preheat the air fryer to 150 degrees Celcius.
Arrange banana slices in the air fryer basket without overlapping each other. Air Fry at 150 degrees Celcius for 15 minutes. Shaking the basket once or twice during cooking time.
Once the chips are ready, transfer them to a bowl immediately while they are hot. Sprinkle salt, pepper, and red chilli powder. Toss them in the seasoning.
Air Fryer Banana Chips are ready to enjoy.