Preheat oven to 350F. Lightly grease and flour a 10 x 15-inch baking ban. Combine sugar, butter and water in a large saucepan. Heat until sugar is dissolved and butter melted.
Add chocolate chips and stir until melted. Add vanilla and set aside to cool. Then, add beaten eggs to chocolate mixture. Mix flour, baking soda, salt and cinnamon and blend these dry ingredients into chocolate until thoroughly mixed. Fold in chopped nuts.
Pour into pan and bake about 40 minutes. Cool, cut, and serve.