In a small bowl, cream butter and sugar until light and fluffy. Beat in the egg, melted chocolate, orange zest and vanilla. Combine the flour, cinnamon, cardamom and salt; gradually add to creamed mixture and mix well. Cover and refrigerate for several hours or overnight.
Shape into 1-in. balls; roll in almonds. Place 2 in. apart on ungreased baking sheets. Flatten with a glass dipped in sugar. Bake at 375° for 8-10 minutes or until lightly set. Remove to wire racks.