Preheat oven to 300 degrees and spray a cookie sheet with nonstick spray.
In a large bowl, cream the butter and sugar together using an electric mixer on high.
Add the egg and vanilla and beat until smooth.
In a separate bowl, combine the flour, salt, baking soda, and cream of tartar.
Pour the dry ingredients into the wet and mix together until dough is formed.
Mix the sugar and cinnamon together in a bowl.
Form the cookie dough into balls (about 2 tablespoons per ball), then roll in the sugar mixture, and then press gently onto the cookie sheet.
Bake for about 13 minutes until golden around the edges. Remove from oven and transfer to rack to cool.
When cookies are completely cooled, microwave chocolate chips in separate bowls and stir until smooth.
Dip cookies halfway into warm chocolate and place on rack or parchment paper and immediately sprinkle with peppermint, sprinkles, or additional cinnamon & sugar.
Let chocolate harden before serving/storing.
