TIGER PRAWN AND FISH STEW

1 tbsp olive oil • 1 leek, finely chopped • 1 small fennel bulb, finely chopped • ½ tsp sweet smoked paprika • 1 tbsp tomato purée • 2 tsp sherry vinegar (or white or red wine vinegar) • 200g tomatoes, roughly chopped (or a 227g can chopped tomatoes) • 500ml Cooks’ Ingredients fresh fish stock • 220g pack Big & Juicy Whole Madagascan Tiger Prawns, defrosted • 4 x 120g white fish fillets (such as cod or hake) • Handful flat leaf parsley, roughly chopped