Heat your dutch oven over medium high heat. Add the olive oil, then add the whole sausage links. Cook for 3-5 minutes until browned on one side, then flip and cook another 3-5 minutes. Remove the sausages, and transfer to a plate to cool while you cook the vegetables. (The sausages won't be cooked through, they will finish cooking in the soup.

In the same dutch oven in the remaining olive oil and fat drippings from the sausages, add the onions, carrots, celery, zucchini, garlic, salt and pepper. Cook for 10 minutes, stirring occasionally, scraping up any brown bits from the bottom of the dutch oven, until the vegetables have softened.

Once the sausages have cooled enough to handle, slice the sausages into half moons. Return to the soup along with the can of diced tomatoes, dried thyme, bay leaf and chicken stock.

Simmer the soup over medium heat for 30-45 minutes, until the vegetables are soft and the sausages are cooked through. Turn off the heat, and add the kale. Allow the kale to cook off the heat and the soup to cool for 5 minutes. Taste for salt and pepper, adjust seasoning if needed. Serve warm.

Leftovers will keep refrigerated in an airtight container for 5 days.