Mix together the flour and baking powder then set aside.
In a large bowl, beat the butter until creamy. Blend in the egg yolks one at a time. Beat in the flour mixture alternately with the milk. The dough will be stiff like a cookie dough. Divide the dough into 10 pieces and shape into balls. Roll each ball into a 20cm circle. Place on baking trays and prick with a fork in several places.
Bake in the preheated oven for 10 to 12 minutes, or until golden brown. Set aside.
Caramel Filling: In a saucepan boil the unopened tins of sweetened condensed milk for 3 hours. Monitor the water closely, to make sure there is always water in the saucepan. Remove the tin from heat and let cool for 10 to 15 minutes.
To Assemble: In a small measuring cup combine the brandy and water.
Place one cake layer on serving plate. Sprinkle with brandy mixture, then spread with the now caramel condensed milk. Sprinkle with nuts. Continue stacking until all layers are used.