01 -
Preheat oven to 350°F (175°C). Line two baking sheets with silicone mats or parchment paper.
02 -
In a bowl, whisk 2 3/4 cups flour, cream of tartar, baking soda, and salt. Set aside.
03 -
Using a stand mixer, cream 1/2 cup butter, 10 tablespoons granulated sugar, and 6 tablespoons powdered sugar until fluffy (2-3 minutes).
04 -
Add oil, water, egg, and 1/2 teaspoon vanilla to butter mixture. Mix well.
05 -
Gradually add dry ingredients to wet ingredients, mixing on low until just combined.
06 -
Scoop dough, roll into balls, place on baking sheets.
07 -
Dip glass bottom in 2 tablespoons sugar, press each dough ball to create a well.
08 -
For filling, mix 6 tablespoons butter, brown sugar, 1/4 cup flour, and cinnamon.
09 -
Fill cookie wells with cinnamon mixture, not quite to the rim.
10 -
Bake 9-10 minutes until edges are lightly golden. Cool on sheets.
11 -
For frosting, beat 4 oz cream cheese and 4 tablespoons butter until smooth.
12 -
Add 1/2 cup powdered sugar and 1/2 teaspoon vanilla, beat until smooth.
13 -
Pipe frosting swirls onto cooled cookies.