2 1/4 cups all-purpose flour 2 tsp baking powder 1/2 tsp sa plus more for topping 1/2 tsp ground cinnamon 3/4 cup unsalted butter , at room temperature 1/2 cup granulated sugar 1/2 cup packed light-brown sugar 2 large egg yolks 1 tsp vanilla extract 1/2 tsp rum extract 1/2 cup eggnog