Toss chicken pieces in a bowl with ⅛ teaspoon of salt and black pepper.
In a 2-quart saucepan over medium-high heat, heat olive oil for 30 seconds. Add chicken and cook for 6 minutes, flipping halfway. Remove and set aside.
If the pot is dry, add ½ tablespoon more oil. Add onions, celery, carrots, garlic, and a pinch (⅛ teaspoon) of salt. Cook, stirring occasionally, for 5 minutes until softened. Stir in flour and cook for 2 minutes, stirring often.
Add broth, chicken, and Italian seasoning. Bring to a boil, then reduce heat to low. Cover and simmer for 20 minutes, stirring occasionally, until carrots are tender.
Uncover and add tortellini. Simmer for 4 minutes.
Stir in spinach and cook for 2 more minutes.
Ladle into a bowl and top with shredded Parmesan
Notes
Read Ahead: This soup cooks quickly, so read through the recipe and ingredient notes before starting. Gather all ingredients ahead of time.
Spinach Swaps: Use arugula instead of spinach, or leave it out. You can also add extra spinach if you like.
Tortellini Options: Fresh tortellini cooks fastest and is easy to find. If using frozen or dried, follow the cooking time on the package.