Hot and sour soup is one of the gems of Thai cuisine, every mouthful bursts with complex flavours. Hot and sour prawn noodle soup is one of the classic versions of a classic dish.
1.Place stock, the water, lime leaves, lemongrass and ginger in a large saucepan; bring to the boil. Reduce heat; simmer, covered, 5 minutes. Remove lime leaves, lemon grass and ginger with a slotted spoon. Stir in paste; return to the boil. Stir in the sauce, juice and sugar.
2.Meanwhile, place noodles in a large heatproof bowl; cover with boiling water, stand for 5 minutes or until tender. Drain.
3.Add buk choy to the stock mixture with mushrooms, prawns and chilli; simmer, uncovered, until prawns change colour. Stir in noodles; simmer, uncovered, until hot. Season to taste.
4.Serve soup with coriander, and a squeeze of lime, if you like.
Recipe is not suitable to freeze. Shelled prawns are available fresh in seafood shops and frozen in supermarkets.