Pat the chicken dry and season with salt, pepper, and Italian seasoning.
Heat reserved sun-dried tomato oil in a soup pot over medium-high heat. Sear chicken 3–4 mins per side. Remove and rest for 10 minutes, then dice.
Deglaze the pot with white wine, scraping up the browned bits.
Add butter and diced onion. Cook 10 minutes until softened.
Add sun-dried tomatoes, garlic, tomato paste, dried herbs, Dijon, and honey. Stir and cook for 5 minutes.
Add chicken broth and bouillon. Blend the broth using an immersion blender until smooth.
Bring to a boil, then reduce to a simmer. Add diced chicken and simmer 15 minutes, partially covered.
Reduce heat to low. Let soup cool 1 minute. Stir in cream and parmesan.
Add tortellini and simmer until cooked.
Stir in spinach last minute until wilted. Serve hot!