25 Days of Christmas Cookies

My dad is a cookie monster at Christmas time, he's like a little kid. One of his favorites is snickerdoodles which unfortunately for him is the one cookie that gives me trouble. What's with the snickerdoodle? The recipe is easy enough. They can either turn out soft, fluffy & delish or flat, hard disk. I blame it on the cream of tartar!
Day 10
Snickerdoodles
Ingredients
1 cup shortening
1 1/2 cups white sugar
2 eggs
2 3/4 cups all-purpose flour
1 teaspoon baking soda
2 teaspoons cream of tartar
1/2 teaspoon salt
2 tablespoons white sugar
2 teaspoons ground cinnamon
Directions
Preheat oven to 375⁰F. In a medium bowl, cream together the shortening and 1 1/2 cups sugar. Stir in the eggs. Sift together the flour, baking soda, cream of tartar, and salt; stir into the creamed mixture until well blended. In a small bowl, stir together the 2 tablespoons of sugar, and the cinnamon. Roll dough into walnut sized balls, then roll the balls in the cinnamon-sugar. Place them onto an unprepared cookie sheet, two inches apart. Bake for 8 to 10 minutes in the preheated oven. Edges should be slightly brown. Remove from sheets to cool on wire racks.