Crumble 6 of the vanilla wafers into the work bowl of a food processor and add lemon zest and rosemary; process cookies to pea gravel size. Add butter and continue to process until thoroughly combined. Crumble in remaining 2 vanilla wafers; pulse until just incorporated. Serve with bread
Recipe by Three Many Cooks at https://threemanycooks.com/conversations/omg-butters/