Mix the Greek yogurt with the sweetened condensed milk well. Place a layer of biscuits in a baking dish and pour the first half of the yoghurt mixture over it. Another layer of biscuits and finally pour the rest of the yogurt over it.
Let the dessert soak in the fridge for a day. Sprinkle the chocolate flakes on top before serving. You can use finished chocolate flakes or you can finely grate dark chocolate yourself.
The dessert is delicious and prepared in no time at all.