Prepare the Cookie Dough:

Preheat Oven: Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper.

Cream the Butters and Sugars: In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.

Add Eggs and Vanilla: Beat in the eggs one at a time, then stir in the vanilla extract until well combined.

Combine Dry Ingredients: In a separate bowl, whisk together the flour, baking soda, baking powder, and salt. Gradually add the dry ingredients to the wet mixture, mixing until just combined.

Prepare the Cinnamon Filling:

Mix Filling: In a small bowl, combine the softened butter, brown sugar, and ground cinnamon until well blended.

Assemble the Cookies:

Roll Out the Dough: On a lightly floured surface, roll out the cookie dough into a rectangle (about 1/4 inch thick).

Spread the Filling: Evenly spread the cinnamon filling over the dough.

Roll Up: Starting from one long edge, roll the dough tightly into a log. Wrap the log in plastic wrap and refrigerate for about 30 minutes to firm up.

Slice Cookies: After chilling, remove the log from the refrigerator and slice it into 1/2-inch thick rounds.

Bake:

Bake: Place the cookie rounds on the prepared baking sheets, spacing them about 2 inches apart. Bake for 12-15 minutes, or until the edges are lightly golden.

Cool: Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

Prepare the Icing:

Make the Icing: In a small bowl, whisk together the powdered sugar, milk, and vanilla extract until smooth.

Serve:

Drizzle Icing: Once the cookies are cool, drizzle the icing over the top.