Start off by cooking your tomatoes down. Add 3 cups of your tomatoes into a soup pot and allow to cook over a low temperature. Let them cook until they become mushy and watery.
Remove the cook tomatoes and place them in a blender, with tomato paste, and blend until smooth. Pour back into your soup pot, then add 1 cup of fresh, diced tomatoes. Then add your chicken broth, butter, sugar, chopped onions, and baking soda. Simmer over low heat for 1 hour.
In a double boiler, warm your cream. Pour the warmed cream into your tomato mixture, and mix. Add in your salt, garlic powder, garlic salt, and seasoning salt if desired. Dish into serving bowls, top with shredded mozzarella cheese, croutons, and dried parsley if desired. Serve and enjoy!