These thousand-layer chocolate chip cookies are made from just about the same ingredients as their compatriots. The difference, though, (and it's a significant one) is portions of dough are stacked on top of each other to create layers of flavor and texture. The tops are then sprinkled with fleur de sel. The resulting treats are flat, crispy, and chewy.
*What is fleur de sel?
Traditionally (but not exclusively) from the French coast of Brittany, fleur de sel is collected from the salt that rises to the surface of shallow pools of seawater. It's expensive, yes. Because it's harvested by hand skimming and only forms under very specific weather conditions, it's unlike most other salts available. You can, however, find flake salts from other parts of the world that will be similar. The appearance and flavor of fleur de sel (and the price) means that it's mostly used as a garnish or finishing salt for recipes like these cookies. A little goes a long way.