Combine the butter, garlic, chilli and 2 tablespoons of oil in a small saucepan. Heat over medium heat until hot. Set aside.
Heat a large frying pan over medium-high heat until hot. Add 1 tablespoon of the remaining oil and the Fioretto®. Cook shaking the pan for 2-3 minutes until the stems are bright green. Add 1 tablespoon of water, cover and cook for 1-2 minutes until just tender. Remove to a plate.
Wipe the pan clean and heat over high heat until hot. Combine the remaining 1 tablespoon of oil and prawns. Season with salt and pepper. Add to the hot pan and cook in batches for 1 minute until they change colour. Add the garlic butter to the pan, return the Fioretto® and add the sherry. Cook shaking the pan for 1 minute. Remove from the heat and scatter over the parsley. Spoon into bowls and serve with crusty bread.