To cut the corn into ribs, stand each cob vertically on a chopping board and use a large sharp knife and a rocking motion through the top to carefully cut through the centre. Then repeat with the same technique, cutting it in half again so you're left with quarters.
Next in a small bowl, mix together the oil, cumin, smoked paprika, harissa paste and black pepper. Brush this over the pieces of corn so all the kernels are coated.
If using an air fryer place the corn ribs as a single layer in an air frying basket with a little space in-between. Cook the corn at 190c for 10-15 minutes. If you're oven baking the ribs, lay the corn on a lined baking tray and bake for 25-30 mins. Check half way through and turn, checking to see they are cooking evenly.
Keep some of the leftover marinade to drizzle over once the corn is cooked.
The oven baked corn doesn't curl up as quickly than using the air fryer - you might want to increase the time slightly if you want them more crispy and curly.
Optional - to give a little extra smoky flavour and charring to the ribs, cook for an extra minute or 2 on a hot griddle pan or directly on a BBQ.
When ready to serve, use a large serving dish and drizzle over the leftover marinade, and a squeeze of lime juice, scatter chopped spring onions parsley and the chilli then you're ready to eat!