CAKE: In a large mixing bowl combine flour, brown sugar, baking powder, baking soda and cinnamon. Add melted chocolate, sour milk, tomatoes, butter, eggs and grated peel. Beat with an electric mixer on low speed till combined. Beat on medium speed for 2 minutes. Pour into greased and floured 13x9x2-inch baking pan. Bake in a 350 oven for 35 to 40 minutes or till a toothpick inserted near the center comes out clean. Cool cake in pan on wire rack. Drizzle glaze over each serving; serve with whipped cream, sprinkled with cinnamon and berries, if desired.
CHOCOLATE GLAZE: Melt chocolate and butter over low heat, stirring frequently. Remove from heat. Stir in sifted powdered sugar and hot water. Stir in additional hot water, if needed, to make of drizzling consistency.