1.Preheat oven to 180°C (160°C fan-forced). Grease deep 19cm-square cake pan. Line base and two opposite sides with foil, grease foil well.
2.Place rice in large saucepan of boiling water. Boil, uncovered, until tender, drain well.
3.Combine rice and remaining ingredients in large bowl, mix well. Press mixture evenly over base and halfway up sides of prepared pan. Place pan on oven tray, refrigerate 30 minutes.
4.To make leek filling. Heat butter in medium saucepan. Cook leek, ginger and coriander, stirring, until leek is soft, cool. Combine leek mixture, egg and cream in large bowl, mix well.
5.Pour leek filling into rice crust. Bake, uncovered, in moderately hot oven about 45 minutes or until browned and firm.
6.To make sesame mushrooms, heat oils in large saucepan, cook garlic and seeds, stirring, until seeds are browned lightly. Add remaining ingredients, cook, stirring, until mushrooms are soft.