Pulse flour, sugar, salt, and baking powder in a food processor. Add butter; pulse to combine. Stir cream, yogurt, egg, and vanilla in a bowl. Stir in flour mixture until smooth. Turn out onto floured parchment. Pat dough into a 6-by-8-inch rectangle. Wrap in parchment; freeze until very firm, 2 to 5 hours.Advertisement
Preheat oven to 375 degrees. Cut out 10 rounds using a cutter. Transfer to parchment-lined baking sheet. Brush with cream. Bake until just golden, 20 to 25 minutes. Let cool; store airtight up to 2 days.