Soak cod in water overnight, change water 3 or 4 times. Rinse. In saucepan, cover cod with cold water, bring to boil. Reduce heat, simmer, covered 20 minutes or until fish flakes. Drain. Meanwhile in another pan cook onion in oil until tender but not brown. Stir in tomato, broth, parsley and pepper. Simmer uncovered 15 minutes. Flake drained cod, gently stir into tomato mixture along with potatoes. Pour into ungreased 1.5 quart casserole, bake covered for 1.25 to 1.5 hours at 350 degrees. Stir once or twice.