Preheat oven to 350°.
In the top of a double boiler, melt the chocolate squares over medium heat. Remove from the stove and let cool.
Cream shortening in a large mixing bowl and gradually add the sugar, beating until light and fluffy.
Add the melted chocolate, eggs, corn syrup, water, peppermint, and vanilla, beating until well blended.
Combine the flour, baking soda, and salt in a bowl.
Gradually add to the chocolate mixture, beating until blended.
Place ½ cup sugar in a bowl.
Roll dough into 1" balls and roll in sugar.
Place on an ungreased cookie sheet and bake at 350° for 10 minutes or until cookies begin to crack.
Remove from oven and let cool on pan 5 minutes. Move cookies to wire rack and let cool completely.