Preheat oven to 350 degrees. Grease and flour a 13x 9x 5 cm baking pan. In a bowl mix together the pecans, carrots, bananas, and coconut. Sift together the flour, baking soda, cinnamon, salt, cloves, and mace. Set aside. In a large bowl beat the brown sugar and butter until light and fluffy. Add the eggs and beat until smooth. Add the vanilla to the milk. Beat the milk mixture into the sugar mixture, one third at a time, alternating with dry ingredients, beginning and ending with the dry ingredients. Fold in the carrot/banana mixture until just incorporated. Pour into the prepared pan and bake in the middle of the oven 30 to 35 minutes, or until a toothpick inserted into center comes out clean. Cool the cake completely, and then frost with cream cheese frosting or dust with sugar. Cut into 24 squares. The cake, frosted or not, freezes wrapped in plastic wrap.