Preheat the oven to 225 degrees F with a rack in the middle of the oven. Grease and flour or line with parchment paper two 8 1/2- by 4 1/2-inch loaf pans.
In the bowl of a mixer, combine the brown sugar, salt, eggs, oil, honey, cinnamon, cloves and allspice and mix, using the flat (paddle) beater at low-medium speed until well blended, 6 to 7 minutes. Add the water and baking soda and continue mixing until blended.
Add the flour 1 cup at a time, letting each addition blend before adding the next. Continue beating for about 10 minutes. The batter will be loose, stringy and very, very sticky.
Pour the batter into the prepared loaf pans, top with nuts and/or fruit, if desired.
Bake 2 to 2 1/2 hours or until done.
Remove to a rack and let cool for 10 to 15 minutes before turning the cakes out of the pans.