Cover peas with water and soak overnight. Drain, rinse and place in a Dutch oven. , Add ham bone, water and remaining soup ingredients except sausage and dumplings. Bring to a boil. Reduce heat; cover and simmer 2 to 2-1/2 hours. , Remove ham bone and skim fat. Remove meat from bone; dice. Add ham and, if desired, sausage to pan. , For dumplings, place flour in a small bowl. Make a depression in the center of the flour; add egg and water and stir until smooth. , Place a colander with 3/16-in.-diameter holes over simmering soup; transfer dough to the colander and press through with a wooden spoon. Cook, uncovered, 10-15 minutes. Discard bay leaf.