Heat the olive oil in a large heavy Dutch oven or soup pot over medium heat. Add the diced onion, carrots, and celery. Sauté for 5 to 6 minutes until the vegetables soften and sweeten. Stir in the minced garlic and Italian seasoning, cooking for 60 seconds until richly fragrant.

Pour in the chicken bone broth, scraping any caramelized fond from the bottom of the Dutch oven. Stir in the shredded cooked chicken and julienned sun-dried tomatoes. Season with fine sea salt, cracked black pepper, and red pepper flakes. Bring the broth to a gentle rolling boil over medium-high heat.

Drop the fresh four-cheese tortellini into the boiling broth. Reduce the heat slightly to medium and simmer uncovered for 3 to 4 minutes until the tortellini float to the surface and become tender and pillowy.

Lower the heat to low. Stir in the heavy cream and grated Parmigiano-Reggiano, stirring constantly until the cheese melts seamlessly into the broth. Add the fresh baby spinach and stir gently for 1 to 2 minutes until just wilted. Remove from the heat immediately, ladle into warmed ceramic bowls, and garnish with fresh basil ribbons, cracked pepper, and shaved parmesan curls.