In a large pot or Dutch oven, heat olive oil over medium-high heat. Add ground turkey and cook, breaking it up with a spoon, until browned. Drain off any excess fat.
Add chopped onion, carrots, and celery to the pot. Cook until softened, about 5-7 minutes.
Stir in minced garlic, dried rosemary, dried thyme, and red pepper flakes. Cook for 1 minute more until fragrant.
Pour in chicken broth and add diced tomatoes (undrained). Bring to a boil, then reduce heat and simmer for 15 minutes, allowing the flavors to meld.
Add cannellini beans and kale to the pot. Cook until the kale is wilted and tender, about 5 more minutes.
Season with salt and black pepper to taste. Serve hot.
Notes
This soup is even better the next day as the flavors continue to develop. You can also add other vegetables like zucchini or spinach.