Step 1
Heat oven to 350 degrees F (175 degrees C). Grease and flour bottom only of a 9x5 inch loaf pan.
Step 2
Cream brown sugar and margarine in a large bowl until it turns light and fluffy. Reserve one tablespoon pineapple juice. Stir in zucchini, pineapple and eggs. Add flour, baking soda, cinnamon, salt, and allspice. blend them well. Fold in nuts. Spread in a prepared pan evenly.
Step 3
Bake them for 60 - 70 minutes, or until you can put a toothpick inserted into center of the loaf and the toothpick comes out clean, and then take them out from pan.
Step 4
Making Glaze: Combine reserved pineapple juice, confectioner sugar, corn syrup and 1/4 teaspoon ground cinnamon. Mix until they become smooth, then spoon over warm loaf. Cool completely on wire rack. Wrap and store in refrigerator.