Ingredients
Method
- Preheat oven to 375°F (190°C) and line two baking sheets with parchment. Beat the butter, shortening, and 3/4 cup sugar with an electric mixer on medium until pale and fluffy, about 2 minutes.
- Beat in the egg and vanilla until smooth and creamy, about 30 seconds.
- In a separate bowl, whisk the flour, cream of tartar, baking soda, and salt. With the mixer on low, gradually add to the butter mixture, beating just until combined.
- Stir the remaining 3 tbsp sugar and cinnamon together in a small bowl. Scoop 1-inch dough balls, roll them in the cinnamon sugar, and place 2 inches apart on the sheets.
- Bake 8 to 10 minutes, until edges are set and centers look soft. Cool on the sheets for 5 minutes, then transfer to a wire rack. Serve warm.
Notes
These cookies are softest the day they're baked but stay fresh in an airtight container for up to 3 days. If your kitchen is warm, chill the dough balls for 10 minutes before baking to reduce spreading. Rolling each ball in cinnamon sugar twice gives a thicker, crunchier crust.
