(The University of Western Australia)
1/2 packet Marie biscuits
2 egg whites
1-2 dessert spoons of caster sugar
1 can sweetened condensed milk
2 egg yolks (put whites aside for meringue)
Lemon juice (fresh or bottled) to taste
To make the crust, crush the Marie biscuits, combine with the melted butter and press firmly into pie or tart dish. Refrigerate.
In a bowl, mix the condensed milk, egg yolks and lemon juice. Lemon rind can be added for extra flavour, and yellow food colouring for a nice yellow colour (especially useful if you're using bottled juice, which can look brownish). Be sure not to add too little juice, since it is the acid in the juice which causes the filling to set when baked. Pour the filling into the crust, refrigerate while you whip the egg whites. Add the sugar and whip until the meringue mixture is stiff enough to form peaks. Arrange on top of the pie, covering all the filling and leaving little peaks sticking up.
Bake the pie at 180°C (350°F) for about 15 minutes, until peaks have gone light brown. This is best served as soon as it cools, but keeps for days in the fridge if you don't mind it getting a little gooey.