Add garlic, and saut 1 minute. Stir in 1/4 teaspoon salt.
Add water and potato; bring to a boil. Reduce heat, and simmer, uncovered, 8 to 10 minutes or until potato is tender.
Add broth, crushed red pepper, and sausage; bring to a boil. Reduce heat, and simmer, uncovered, 10 minutes. Stir in remaining 1/4 teaspoon salt and kale, and simmer 8 to 10 minutes or until kale is tender.