How to make
Blend all of the walnuts very finely in a blender. Then add the cocoa and blend a bit more, to mix the 2 ingredients well. Add the dates to the blender and blend until homogeneous.
Distribute the mixture into a rectangular tray, cover with transparent plastic wrap and smooth out well. Put away in the freezer for 30 min.
Melt the chocolate in a water bath and pour it over the now tightened mixture. Put away for another 30 min., this time in the fridge.
Take the dessert out of the tray, remove the plastic wrap, cut it into squares and serve.
