1.  Beat butter and sugar in large bowl on medium speed until fluffy. Beat in egg, vanilla, baking powder and salt.  On low speed beat in flour until blended. 
2.   Remove half the dough, cut in half and wrap individually.  Mix melted chocolate into remaining dough.  Cut dough in half and wrap individually.  Chill until firm, at least 2 hours.
3. Dampen flat surface and cover with two 10-in.-long sheets plastic wrap.  Sprinkle wrap with flour.  Roll out each half of, plain dough on sheet of plastic wrap to form an 8 x 6-in. rectangle.  Repeat with chocolate dough on another 2 sheets plastic wrap.
4. Flip 1 piece of chocolate dough on top of  each of plain dough.  Peel off wrap.   Gently press down on dough with a rolling pin.  Roll each up from a long side into an even log, peeling wrap from plain dough as you roll (make sure center is tight).  Wrap individually and refrigerate 8 hours or up to 3 days.
5. Heat oven to 350°F.
6.  Cut logs into ¼ in.-thick slices.  Place 1 in.apart on greased cookie sheets.  Bake until lightly brown around edges, 10 to 12 minutes.  Cool cookies on sheet on a wire rack 3 minutes
 

¼ cup shortening
¼ cup sugar
1 egg yolk
1 tsp. vanilla extract
1 Tbs. orange rind, grated
1 tsp. lemon juice
1 ¼ cups sifted cake flour
Dash of salt
Chopped nuts
Candied cherries
1 egg white

Cream the shortening and the sugar thoroughly.  Add egg yolk, vanilla extract, orange rind and lemon juice.  Beat well.  Add flour which has been sifted with the salt.  Form into balls the size of large marbles.  Dip into the slightly beaten egg white and roll in chopped nuts.  Place 1 ½ inches apart on greased cookie sheet.  Press half a candied cherry on top of each cookie.  Bake in a gas oven 350°F. for 20 to 25 minutes.  Yield: 3 ½ dozen.