Gather all your ingredients and tools. Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a small bowl, combine the softened butter, light brown sugar, flour, ground cinnamon, and a pinch of salt. Mix until smooth and freeze for 10 minutes.

In a medium bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt. In a larger bowl, beat the softened butter and granulated sugar until light and fluffy.

Add the egg and vanilla extract to the butter mixture, beating until fully combined.

Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Avoid overmixing.

Divide the cookie dough in half. Press one half into the bottom of a bowl or plate, drop small pieces of cinnamon filling on top, then cover with the remaining dough.

Gently fold the layers to create a marbled effect.

Portion the marbled dough into 2-tablespoon-sized balls and freeze for 10 minutes.

Arrange dough balls on the prepared baking sheet, spacing them 2 inches apart. Bake for 10-12 minutes until edges are set.

Cool on a wire rack before enjoying.