How to Make Mexican Hard Milk Candy

1). Rub the baking dish with butter and set aside.
2). Place milk in a sauce pan, add sugar and cream of tartar. Cook over low heat until the sugar is dissolved. Stir constantly.
3). Bring to a boil over low to medium heat and cook for about an hour and a half. Do not leave the kitchen while the candy is cooking, and stir often. The candy will start to pull away from the sides of the pan and the temperature should be 236 degrees F on a candy thermometer to be finished.
4). Take the pan off the heat and add pecans. Stir until they are all mixed in and pour the mixture into baking dish. Allow to cool and cut into squares.