In a large bowl, whisk together flour and salt.

In the bowl of a mixer fitted with the paddle attachment, add the butter and cream cheese. Mix on medium speed until light and fluffy, about 2 minutes, scraping down the sides as needed. Add the sugar and vanilla, and mix until well combined. Add the flour and mix on low speed until just combined (do not over mix). Mix in the toasted walnut pieces.

Transfer dough to a work surface and divide in half. Shape each half into a log, 8 1/2 inches long and 2 inches in diameter. Wrap each log in parchment paper and freeze overnight or up to 2 weeks.

Position oven racks in the upper and lower thirds of the oven. Preheat the oven to 350 degrees F. Take out one log from the freezer and let it set out for 30 minutes. Unwrap the log and roll it in the remaining chopped walnuts, coating completely. Slice into 1/4-inch rounds. Space 1 in apart on baking sheets lined with parchment paper or a silpat.

Bake cookies for 18 to 20 minutes, rotating halfway through, until golden around the edges. Let cookies cool completely on the baking sheets on wire racks. (Do not remove cookies from baking sheet until completely cooled). Repeat with remaining log and walnuts. Store cookies in a airtight container at room temperature up to 3 days.