In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.

In a large bowl, using an electric mixer, cream together the softened butter, granulated sugar, and 1/4 cup light brown sugar until light and fluffy (about 2-3 minutes).

Beat in the egg and vanilla extract until well combined.

Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined and a soft dough forms. Do not overmix.

Form the dough into a disk, wrap it tightly in plastic wrap, and refrigerate for at least 30 minutes (or up to 2 hours). This makes the dough easier to handle.

While the dough chills, prepare the filling. In a small bowl, combine the 1/2 cup packed light brown sugar and ground cinnamon. Stir in the melted butter until it forms a thick, spreadable paste.

Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper.

On a lightly floured surface or between two sheets of parchment paper, roll out the chilled cookie dough into a rectangle, approximately 12x8 inches and about 1/8 to 1/4 inch thick.

Evenly spread the cinnamon swirl filling over the entire surface of the dough, leaving a small 1/2-inch border along one of the longer edges.

Starting from the long edge opposite the border, carefully roll the dough into a tight log. Pinch the seam gently to seal.

Using a sharp knife or bench scraper, slice the log into 1/2-inch thick rounds. You should get about 24-30 cookies.

Place the cookie slices 1-2 inches apart on the prepared baking sheets.

Bake for 10-12 minutes, or until the edges are lightly golden and the centers are just set. Do not overbake to keep them soft and chewy.

Let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.

While the cookies cool, prepare the glaze. In a small bowl, whisk together the softened cream cheese, powdered sugar, 1 tablespoon of milk/cream, and 1/2 teaspoon vanilla extract until smooth. Add more milk/cream a teaspoon at a time if needed to reach a drizzle-able consistency.

Once the cookies are completely cool, drizzle the cream cheese glaze generously over each cookie. Allow the glaze to set for a few minutes before serving.