Step 1

Place the flour, walnuts, rosemary, sugar and salt in the bowl of a food processor. Pulse until the walnuts are finely ground. Add the parmesan. Pulse a few times to combine.

Step 2

Toss in the butter cubes and process until the dough comes together. Dump the dough onto a sheet of plastic wrap or waxed paper. Form the dough into a 12" log. Wrap and refrigerate for at least 1 hour or up to 3 days. At this point the dough can be frozen for up to 3 months.

Step 3

When you're ready to bake, preheat the oven to 375°F. Line a 1/2 sheet pan with parchment paper or a silicone baking mat.

Step 4

Slice the log into 1/4" thick rounds. Line the cookies on the prepared sheet pan about 1/2" apart.

Step 5

Brush the tops of the cookies with egg white and then press 2 rosemary leaves onto each cookie.

Step 6

Bake the cookies until they are lightly browned and center is set, about 10-12minutes. If you're oven bakes unevenly, rotate the tray halfway through baking.