In a large Dutch oven, heat the olive oil over medium heat.
Add the sliced chicken sausage. Cook for 4 to 5 minutes, stirring occasionally, until lightly browned.
Add the onion, carrots, and celery. Cook for 5 minutes, stirring occasionally.
Add the garlic, Italian seasoning, and crushed red pepper flakes. Cook for 30 seconds, stirring constantly.
Add the cannellini beans, diced tomatoes, and chicken broth.
Increase the heat to medium-high and bring the soup to a boil.
Reduce the heat to medium-low. Cover and simmer for 15 minutes.
Add the kale, salt, and black pepper. Simmer uncovered for 5 to 7 minutes, or until the kale is tender.
Add the lemon juice and stir well.
Remove the Dutch oven from the heat.
Notes
Serving Size: 1⅔ Cups
Tips and Tricks
Cut the vegetables evenly - Similar-sized pieces help the carrots, celery, and onion become tender at about the same time.Adjust the broth after storing - The beans and vegetables may absorb some broth in the refrigerator. Add a small amount of broth when reheating if needed.
Storing and Reheating
Refrigerate - Store cooled soup in an airtight container in the refrigerator for up to 4 days.Freeze - Freeze cooled soup in freezer-safe containers for up to 3 months. Leave a little room at the top for expansion.Reheat on Stovetop - Place the soup in a saucepan and warm over medium-low heat, stirring occasionally, until heated through.Reheat in Microwave - Place one serving in a microwave-safe bowl and heat until hot, stirring partway through.