Gnocchi are potato dumplings that add a comforting contrast to the other earthy ingredients in this soup. Smarts: This soup is absolutely loaded with ingredients, so you'll need the full amount of stock listed. Leaving the lid on and slightly ajar while the soup simmers will help prevent too much liquid from evaporating off during cooking.
Heat a large Dutch oven with oil over medium heat. Add mushrooms and saute until mushrooms are deep golden brown, 4 to 6 minutes. (Don’t rush this step. Browning the mushrooms will add flavor to the soup.)
To the mushrooms, add onions, kale stems (reserve leaves), Italian seasoning, red pepper flakes, and some salt. Saute until onions are starting to soften, 2 to 3 minutes more.
Add vinegar, scraping up any brown bits on the bottom of the pan.
Stir in kale leaves, stock, tomatoes (including liquid), and parmesan rind.
Bring soup to a simmer. When soup is simmering, add the lid to the pan and reduce heat to low. (If the soup bubbles over, move the lid so it is slightly ajar.) Simmer soup, covered, for 10 minutes to let the flavors come together.
Remove lid and add gnocchi and beans. Simmer gnocchi according to package directions, usually 3 to 4 minutes.
Remove parmesan rind from soup. Taste and season soup with some salt and pepper.
Ladle soup into bowls and top with grated cheese. Enjoy!