Preheat oven to 350 degrees. Prepare 3 muffin pans by spraying with nonstick cooking spray or lining with paper liners. In a large bowl, mix together flour, baking soda, salt and bran. In another medium bowl, mix together melted, cooled butter, brown sugar, molasses, zucchini, sour cream and milk. Mix wet into dry ingredients and then gently fold in blackberries. Full muffin cups 2/3 full and bake 28-30 minutes or until a toothpick inserted into the center comes out clean.
