In a small bowl, combine the softened butter, brown sugar, and ground cinnamon. Mix until you have a thick paste.
Roll the mixture into small marble-sized balls (about ½-inch in diameter). Place them on a parchment-lined baking sheet and pop them in the freezer for at least 30 minutes or until firm.

In a large mixing bowl with a hand mixer or in a stand mixer, beat the softened butter and white sugar together until light and fluffy.

Add the eggs and vanilla extract, mixing until well combined.

In a separate bowl, whisk together the gluten-free flour, baking soda, salt, and cream of tartar.

Gradually add the dry ingredients to the wet ingredients, mixing until a soft dough forms. Once the cinnamon marbles are frozen, add them to the cookie dough and mix on low speed until just combined.

In a small bowl, mix together the white sugar and cinnamon for the cinnamon sugar coating.

Scoop out about 2 tablespoons of cinnamon roll cookie dough and roll it into a ball. Roll each ball in the cinnamon sugar mixture until well coated.

Place the coated dough balls on a parchment-lined baking sheet, leaving about 3 inches of space between each one.

Preheat your oven to 350 degrees F.

Bake the cookies for 11-12 minutes, or until the edges are just set and slightly golden.

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

Pour yourself a glass of milk, grab a few cookies, and enjoy the best of both worlds—all in one delicious bite!