Sauté the Vegetables: Heat the olive oil in a large stockpot or Dutch oven over a medium heat. Add the chopped onion, carrots, and celery. Cook for 6-8 minutes, stirring occasionally, until the vegetables have softened and the onion is translucent.

Add Aromatics: Add the minced garlic, dried oregano, and dried thyme to the pot. Cook for another minute until fragrant, being careful not to let the garlic burn.

Thicken the Base: Sprinkle the plain flour over the vegetables and stir continuously for one minute. What works best for me is to really cook out that raw flour taste; this step is key to creating a velvety, thick broth later on.

Create the Broth: Gradually pour in the chicken stock, stirring constantly to prevent any lumps from forming. Bring the liquid to a gentle simmer.

Poach the Chicken: Season the broth with a good pinch of salt and pepper. Carefully place the whole chicken breasts into the simmering stock. Reduce the heat to low, cover the pot, and let the chicken poach gently for 15-20 minutes, or until cooked through and no longer pink inside.

Shred the Chicken: Carefully remove the cooked chicken breasts from the pot and place them on a cutting board. Using two forks, shred the chicken into bite-sized pieces. Set aside.

Cook the Tortellini: Bring the broth back to a steady simmer. Add the fresh tortellini to the pot and cook according to the package directions, which is typically about 3-4 minutes. The tortellini will float to the surface when they are nearly done.

Finish the Soup: Reduce the heat to low. Stir in the double cream, the grated Parmesan cheese, and the shredded chicken. Stir gently until the cheese has melted and the soup is creamy. Do not let the soup boil after adding the cream.

Wilt the Spinach: Add the fresh spinach to the pot and stir for 1-2 minutes, just until it has wilted into the hot soup.

Serve: Taste the soup and adjust the seasoning with more salt and pepper if needed. Ladle into warm bowls, garnish with fresh parsley and an extra grating of Parmesan cheese.