01 -
Combine yolks, flour, and milk using your stand mixer's hook until everything looks blended. Drop in the soft butter and keep mixing until you've got a unified dough.
02 -
Move the mixture to your counter and work it with your hands until it feels smooth and sticks together nicely.
03 -
Wrap in some baking paper and stick it in the fridge for 2 hours so the dough can chill out.
04 -
Get your oven hot at 200°C.
05 -
Take your cold dough and cut it into 12 same-sized chunks.
06 -
Grab your rolling pin and flatten each chunk into circles about 20-22 cm across. Keep the extra pieces covered so they don't dry out.
07 -
Stab each circle with a fork a few times to stop them puffing up when they cook.
08 -
Pop each one in the oven for 7 minutes till they're slightly golden. They'll be super fragile, so be careful moving them to cool on your wire rack.
09 -
Split your eggs and put the whites in a bowl. Leave them out covered at room temp all night to make them more stable.
10 -
Put your egg whites and icing sugar in your mixer bowl. Set this over some steaming water and stir gently until all the sugar melts. Aim for about 55-60°C if you've got a thermometer.
11 -
Move your bowl to the mixer and whip at medium speed until everything cools down and the mix forms soft peaks.
12 -
Put one pastry circle on your serving plate and smear 2 big spoonfuls of caramel milk spread all over it.
13 -
Carefully put another circle on top. Don't worry about small breaks - the caramel will hide them.
14 -
Keep adding caramel and pastry circles, making sure you end with pastry on top.
15 -
Put your stacked cake in the fridge overnight so all the flavors can mingle and it firms up.
16 -
Spread your fluffy egg white mixture all over the cake, making pretty spikes if you want.