Hearty Hamburger Soup

2 lbs lean ground beef
1 white onion, peeled and diced
1/4 teaspoon ground black pepper, more to taste
1/2 teaspoon dry oregano, more to taste
1/2 teaspoon dry basil, more to taste
1/4 teaspoon seasoning salt
1 (1 1/2 ounce) envelope onion soup mix
6 cups water, more to desired consistency
1 (8 ounce) can tomato sauce
1 tablespoon soy sauce
1 (15 ounce) can diced tomatoes, undrained
1 (15 ounce) can corn, drained
1 cup celery, sliced
1/4 cup celery leaves, coarsely chopped
1 cup fresh carrot, sliced
1 cup white potato, peeled and cut into small cubes
garlic salt, to taste
shredded parmesan cheese, to serve
sour cream, to serve