1 tablespoon olive oil
2 onions, chopped
2 tablespoons unbleached all-purpose flour
3 cups chicken broth
2 cups water
4 large potatoes, peeled and cubed
1 teaspoon dried marjoram
1 teaspoon mustard powder
1/4 teaspoon curry powder
1/4 teaspoon celery seeds
1/4 teaspoon freshly ground black pepper
1 2/3 cups milk
1/2 pound fully cooked lean ham, cut into 3/4" pieces
6 scallions, sliced