Heat 1 tablespoon olive oil in a frypan over medium-high heat. Stir in scallops; cook, turning until white on all sides. Drain and set scallops aside to cool.
Place into a food processor the onion, garlic, sun-dried tomatoes, egg, and 1 tablespoon olive oil. Then add parsley, basil leaves, chillis and Italian herbs. Pulse on medium setting until finely chopped.
Place scallops, tuna and prawns into food processor and pulse on low. Gradually pour in breadcrumbs, continuing to pulse until the mixture becomes firm and slightly sticky but is not pureed to a paste (the seafood should maintain some texture).
Form the mixture into palm-size patties about 2-3cm thick. Place on a plate, cover and refrigerate for 1 hour.
Heat 2 tablespoons olive oil in a large frypan over medium heat. Coat patties lightly in flour; shake off excess flour and place patties in frypan. Cook until golden brown on both sides.