Shake the water and 1/2 cup of the flour in a sealed container or a jar to blend the flour and water well and avoid lumps.
Thicken the flour/water mix over low heat, stirring constantly, until it reaches the consistency of paste. Remove from heat and let cool.
Mix syrup, salt, vanilla, cocoa/carob and oil. Then add the rest of the flour-water mixture. Mix well.
Add the remaining 1 1/2 cups of flour, baking powder and the nuts or chocolate chips, if you choose to add those.
Spread mixture into a greased 11 x 7 pan. Bake at 350 for 25 minutes, or until a knife can be inserted and come out clean.