Smash the biscuits into a fine crumb either by hand or in a food processor.

Stir in the melted butter and then press the mixture into the bottom of a greased 22cm tart tin.

Mix the egg yolks together with the condensed milk until the mixture is smooth and then stir in the lemon juice. Mix it very well until it's nice and even.

Spread the egg mixture over the crumb base and refrigerate until chilled.

Meanwhile, beat the egg whites until they are stiff and then gradually add the sugar. Continue beating until it makes a shiny meringue.

Spread the egg white over the lemon layer.

Use a blow-torch to gently brown the top of the meringue (optional).

Refrigerate until it is chilled.

Remove the tart from the tin, slice it up and serve with whipped cream and/or vanilla ice cream.