01 -
Add the butter, granulated sugar, and brown sugar to the bowl of a stand mixer or hand mixer fitted with the paddle attachment. Beat on medium-high speed for 2-3 minutes. Add the vanilla and eggs, and beat for another 1-2 minutes until light and fluffy.
02 -
Whisk the dry ingredients (cake flour, cornstarch, baking soda, baking powder, and kosher salt) in a medium bowl until combined. Add the dry ingredients to the wet mixture and beat on medium speed until combined, about 1-2 minutes, stopping to scrape down the sides of the bowl. Cover and chill the dough for one hour.
03 -
Preheat the oven to 175°C (350°F) and line two large baking sheets with parchment paper.
04 -
In a medium bowl, stir together the filling ingredients (butter, brown sugar, cinnamon, and cake flour) until smooth. Use a heaping teaspoon to scoop the filling and roll into small balls. Place the balls on a baking sheet.
05 -
Scoop out the chilled dough using a 1/4 cup measure (or large cookie scoop). Divide in half, create a well in one half, place a filling ball in the center, and press the remaining dough on top. Pinch the seams and roll into a ball to seal the filling inside.
06 -
Arrange the stuffed cookie dough balls on the prepared baking sheet, keeping them about 5 cm apart. Bake for 11-13 minutes, until the tops are just set and the edges are lightly golden. Cool on the baking sheet for 5 minutes, then transfer to a wire rack.
07 -
In a small bowl, whisk together the powdered sugar, cinnamon, melted butter, and milk until smooth. Place parchment paper under the cooling rack, then spoon the glaze onto the cookies, letting it spread to the edges. Allow the glaze to set for 15 minutes before serving.