In a large pot or dutch oven, melt butter or heat olive oil over medium heat. Add the chopped onion and thinly sliced carrots, then cook until soft and fragrant, about 6–8 minutes. Season with salt, black pepper, and parsley flakes.
Stir in minced garlic and cook for 1–2 minutes until fragrant, being careful not to burn it.
Pour in the chicken broth or chicken stock, scraping the bottom of the pot to release flavor. Bring to a boil over medium-high heat, then add the raw chicken. Boil until the chicken is cooked through, about 15–20 minutes.
Remove the chicken and place it on a cutting board. Shred it into bite-sized pieces using two forks and set aside.
Add the orzo pasta and fresh lemon juice to the pot. Stir and cook uncovered for about 10 minutes, or until the orzo is al dente. Add a splash of broth if the soup thickens too much.
Return the shredded chicken to the pot. Stir in italian seasoning, salt, black pepper, and a splash of heavy cream. Mix well and let the soup simmer for 5 minutes over medium heat.
Stir in optional ingredients like fresh spinach, lemon zest, parmesan cheese, or red pepper flakes. Taste and adjust seasoning as needed.
Ladle into bowls and garnish with fresh parsley and extra lemon wedges. Serve warm with crusty bread and enjoy the perfect zing of lemon and creamy texture.