Melt the butter and oil together in a frying pan. Add the garlic, chilli and paprika, then fry for 1-2 mins until starting to turn golden. Turn up the heat, throw in the prawns and fry for a few mins, stirring, until all the prawns turn pink. Take off the heat, season and stir in the lemon juice and parsley.
Add some lemon slices to a finger bowl of warm water, grab a bowl for the shells, then dig straight in with your fingers and hunks of crusty bread.