65g2½oz milk or white chocolate buttonsI used broken up white chocolate
Lightly butter 3 baking trays. Break up the chocolate and gently melt it along with the butter in a heatproof bowl set over a pan of barely simmering water or in a microwave, taking care not to burn the chocolate, stirring occasionally. Stir in the condensed milk, then remove from the heat and cool.
Mix in the flour and the chocolate buttons and chill the mixture until firm enough to handle. Preheat the oven to 180C / fan 160C / gas 4.
Place large teaspoonfuls of the mixture spaced well apart on the prepared baking trays. Bake in the preheated oven for about 15 minutes. The cookies should still look soft and will glisten. Don't overcook them, as they soon become very hard. Carefully remove the cookies with a palette knife and cool on a wire rack.
I do bake these for 7 mins then remove from the oven and give the whole tray a bang on the side and then back in for the last 8 mins i find it just removes any air and gives the crack effect along the top.