Preheat oven to 375 degrees F (190 degrees C). Grease cookie sheets.
In a large bowl, cream together the shortening, peanut butter, brown sugar, and 1 cup white sugar until smooth. Beat in the eggs one at a time, and stir in the milk and vanilla. Combine the flour, baking soda, and salt; stir into the peanut butter mixture until well blended. Shape tablespoonfuls of dough into balls, and roll in remaining white sugar. Place cookies 2 inches apart on the prepared cookie sheets.
Bake for 10 to12 minutes in the preheated oven. Remove from oven, and immediately press a chocolate kiss into each cookie. Allow to cool completely; the kiss will harden as it cools.