Coronation prawn and mango cocktail

Method

1. Heat the sunflower oil in a small saucepan, add the onion and cook over a low heat for 5 minutes, until soft but not browned. Add the curry powder and cook for 1 minute. Add the tomato purée, 2 tablespoons of the lemon juice, the mango chutney and 150ml water and simmer for 20-25 minutes, stirring occasionally, until reduced to a thick sauce. Transfer to a mini food processor and blend until smooth. Leave to go cold.
2. Put the mayonnaise and yogurt into a bowl with the cold curry sauce and mix well. Season, then stir in the remaining lemon juice to taste.
3. Divide the lettuce leaves between 4 wine glasses or glass bowls and arrange the slices of avocado, mango and the prawns on top. Drizzle with 2 tablespoons of the sauce and serve with lightly buttered brown bread, if you like.