In a large bowl, cream the butter and brown sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in coffee. Combine the flour, baking soda, salt and nutmeg; gradually add to the creamed mixture and mix well. Stir in apple butter and walnuts (dough will be soft). Refrigerate for 1 hour.
Drop by teaspoonfuls 2 in. apart onto lightly greased baking sheets. Bake at 400° for 10-12 minutes or until edges are firm. Remove to wire racks to cool.
This recipe was tested with commercially prepared apple butter.