In a large skillet over medium-high heat, saute onion, green pepper and celery in butter until tender. Add bay leaf, tomatoes, brown sugar, basil, salt and pepper; cover and simmer for 5-10 minutes. , Meanwhile, for dumplings, combine flour, baking powder and salt in a bowl. Cut in butter. Add parsley and milk; stir just until mixed., Drop by tablespoonfuls onto the simmering tomato mixture, creating six mounds; cover tightly and simmer for 12-15 minutes or until a toothpick inserted into one of the dumplings comes out clean. Discard bay leaf. Serve immediately.