Add butter and granulated sugar to the bowl of a stand mixer fitted with the paddle attachment; mix at medium speed until pale and fluffy, about 2 minutes. Mix in the egg and vanilla extract.
Reduce speed to low. Add flour, rosemary, and salt, and mix until combined.
Halve dough and shape each half into a log. Place each log on a 12-by-16-inch sheet of parchment. Roll dough in the parchment until the diameter reaches 1½-inches by pressing a ruler along the long edge of parchment at each turn to narrow the log.
Transfer to paper-towel tubes to keep the shape, and refrigerate until firm, about 1 hour.
Preheat oven to 375.
Roll each log of dough in raw sugar. Cut into 1/4-inch-thick rounds. Space rounds 1-inch apart on baking sheets lined with parchment. Bake until edges are golden, 10 to 15 minutes. Let cool on sheets on wire racks.
Store in airtight containers at room temperature up to 3 days. Enjoy!