For the herb mix, heat a frying pan until hot then add the olive oil and onion, then sweat until soft.
Place the herbs in a bowl and pour over boiling water to cover. Drain immediately through a sieve and squeeze out the excess water. Discard the water.
Place the herbs into a food processor along with the onion, black pepper and red peppers. Blend to a purée.
For the monkfish, preheat the oven to 190C/375F/Gas 5.
Remove the cartilaginous bone from the monkfish tails but leave 5cm/2in attached to the flesh at the end of the tails.
Season the first tail inside and out and add half of the herb and pepper mix.
Bring the two halves of each tail together sandwiching the mix.
Lay four slices of the prosciutto on a flat surface side by side. Lay the tail on the prosciutto and wrap it around the fish. Repeat with the second tail. Allow to rest in the fridge for one hour.
Heat a frying pan until hot then add the olive oil and seal the fish on each side.
Place in the oven for 15 minutes or until cooked through. Serve.