Boston brown bread

Name: Authentic Boston Brown Bread Recipe
Prep time: 15 min
Cook time: 150 min
Yield: 8
Cuisine: United States
Ingredients: 1 cup rye flour; 1 cup yellow cornmeal; 1 cup whole wheat flour; 1 teaspoon baking soda; 1/2 teaspoon salt; 1/2 cup molasses; 1 1/2 cups buttermilk; 1/2 cup raisins (optional)