root beer float cookies

Have you ever heard of such a thing?  My kids loved them.  They had some quickly right before bed but tonight I think we'll do it right and put some vanilla ice cream between them for an ice cream sandwich.  These would make a great conversation piece at a picnic or bbq.

root beer float cookies (blog: Heat Oven to 350)
1 cup unsalted butter at room temperature
1 cup granulated sugar
1 cup packed light brown sugar
1 large egg
1/2 cup vegetable oil
2 tablespoons milk
1 teaspoon vanilla
1 tablespoon plus 2 teaspoons root beer concentrate
3 1/2 cups flour
1 teaspoon cream of tartar
1 teaspoon baking soda
1/8 teaspoon salt
1 1/2 cup white chocolate chips

Preheat oven to 350 degrees.  Place butter and sugars in large bowl.  Using electric mixer at medium speed, cream.  Beat in egg.  Continue to beat until mixture is fluffy.  Beat in oil, milk, vanilla and root beer concentrate.
In a large bowl whisk together flour, cream of tartar, baking soda and salt.  Add to butter mixture and mix until combined.  Fold in vanilla chips.
Roll into balls and place on ungreased cookie sheets.  Bake 10 minutes.  Let cool 5 minutes on the cookie sheet and then remove to a wire rack to cool completely.  Made 4 dozen.