In large bowl, combine peanut butter and shortening; beat well. Add brown sugar and sugar; beat until well blended. Add vanilla and eggs; blend well. Add milk and corn syrup; mix well.
Lightly spoon flour into measuring cup; level off. In small bowl, combine flour, baking powder, baking soda and salt; mix well. Add to peanut butter mixture; mix well. Cover with plastic wrap; refrigerate at least 2 hours for easier handling.
Heat oven to 375°F. Shape dough into 1-inch balls. Place 2 inches apart on ungreased cookie sheets. Flatten in crisscross pattern with fork. If necessary, dip fork in sugar to prevent sticking.
Bake at 375°F. for 7 to 9 minutes or until light golden brown. Immediately remove from cookie sheets. Cool completely.