Prepare the filling: Beat softened cream cheese, 1/4 cup sugar, and 1 tsp vanilla until smooth. Drop 14 tablespoon-sized scoops onto a parchment-lined plate. Freeze for at least 1-2 hours until completely solid.

In a medium bowl, whisk together flour, baking soda, cream of tartar, salt, and 1 tsp cinnamon. Set aside.

In a large bowl, cream the softened butter, brown sugar, and 1/2 cup granulated sugar until light and fluffy (about 2 minutes).

Beat in the eggs one at a time, followed by 2 tsp vanilla extract.

Gradually add the dry flour mixture to the wet ingredients, mixing on low speed just until combined. Do not overmix.

In a shallow bowl, whisk together the remaining 1/3 cup sugar and 1.5 tbsp cinnamon for the coating.

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

Take about 2.5 tbsp of cookie dough, flatten it, and place a frozen cream cheese ball in the center. Carefully wrap the dough around the filling, pinching the seams completely shut. Roll into a smooth ball.

Roll the stuffed dough ball generously in the cinnamon-sugar mixture. Place on the baking sheet 2 inches apart.

Bake for 12-14 minutes until edges are set but centers are still soft. Cool on the pan for 10 minutes before serving warm.