1.Preheat oven to 220°C/425°F. Oil four 1¼-cup (310ml) ovenproof dishes.
2.In a large frying pan, heat half the oil; cook onion and ginger; stirring, until onion softens. Add paste; cook, stirring, until fragrant. Add stock and tomato; bring to the boil, simmer, uncovered, about 5 minutes or until tomato is tender. Remove from heat. Stir in prawns, peas and coriander; season. Spoon mixture into dishes.
3.Cut two 9cm rounds from each roti bread. Place over filling. Brush with remaining oil. Bake pies, uncovered, about 15 minutes or until browned and crisp.