To create the impressive wave pattern on the florentine cookies, Thomas Keller uses a tile comb (if purchased from a hardware store) or if you'd prefer a baking-specific tool, it is referred to as an icing or decorating comb. Note, for this recipe you need a comb that has a rectangle edge, not triangle.
This is an inexpensive tool and worth having for more than just the cookie recipe. Cake decorators use it to smooth out buttercream or create patterns on the sides of their cakes.
- Sur la Table- Union Square location, online, Amazon
I purchased this Ateco metal version from Sur la Table. Ateco also makes a plastic version but after doing some research, found that the metal version will give a cleaner look particularly on cakes.
- Lowes (thanks Leticia)- surprisingly a hardware store is one of the best places to get baking equipment. Leticia found this tile comb at a bargain for $2.