4 tablespoons (1/2 stick) butter softened
2/3 cup all-purpose flour (add an extra tablespoon if dough seems a little loose)
1/2 teaspoon cream of tarter
1/4 teaspoon baking soda
1/8 teaspoon salt
3 tablespoons white sugar
3 tablespoons packed brown sugar
1 large egg yolk plus 1 1/2 teaspoons egg white
1/2 teaspoon vanilla extract
2 tablespoon white sugar
1 teaspoon cinnamon
Directions: Pre-heat oven to 400 degrees. Line a cookie sheet with parchment paper.
In a small bowl mix flour, cream of tarter, baking soda and salt.
In another bowl cream butter and both sugars and beat until light and fluffy. Beat in egg and vanilla. Mix in flour until just combined, (this is where you would add your extra tablespoon of flour if you felt you need to).
Cover dough and chill in fridge or freezer 10-15 minutes.
In a small bowl, mix extra sugar and cinnamon. Roll chilled dough into balls and then roll in sugar/cinnamon mixture until generously coated. Place on cookie sheet about 2 inches apart and bake about 8 minutes, until edges start to brown but middles are soft and puffy. Do not overbake. Cool on cookie sheet 3 minutes and then transfer to wire rack to cool completely.
I get 10 good sized cookies out of this batch.