Combine biscuit crumbs, walnuts and butter. Press into the base of a 22 cm spring form pan. Chill for 20 mins.
Beat PHILADELPHIA cream cheese until smooth, add caster sugar, sour cream, eggs, lemon juice, cornflour and lemon rind, beat well.
Pour into prepared crumb crust and bake in oven 140 °C for 60 minutes. Allow to cool in oven. Chill for 2 hours.