In a bowl, whisk together the flour, baking powder, and salt. Set aside. In a bowl of a stand mixer, beat the butter and sugar on high.
Next, beat in egg and vanilla until incorporated. Turn mixer on low and gradually add in flour mixture. Mix until combined.
Divide the dough into two equal parts.
Remove top piece of parchment paper. Spread one tablespoon of melted butter onto each rectangle.
Mix 1/4 cup sugar and cinnamon together then sprinkle evenly over each.
Slowly roll up each rectangle tightly into a 9-inch log, peeling the dough off of the bottom piece of parchment paper. It’s okay if the dough cracks slightly, smooth out any cracks with your fingers. Cover the dough log in plastic wrap and chill for 2 hours.
Preheat oven to 350°F. Line a cookie sheet with parchment paper. Remove dough logs from the refrigerator. Use a sharp knife to cut into 1/2″ thick slices. Place slices onto baking sheets about 2 inches apart. Bake for 10-12 minutes, until lightly browned on the sides. Make the glaze.