This healthy and creamy soup recipe is just so good.
In a big pot over medium heat, heat oil. Add onion and celery and cook 'em until they're soft, about 6 minutes. Add garlic and red pepper flakes (if you're using them) and cook until fragrant, one minute more.
Add chicken broth and lemon juice to the pot and bring to a boil. Add chicken breasts and turn the heat down. Let everything simmer until the chicken is cooked through, 10 to 12 minutes.
Take the chicken out of the pot and shred it with two forks. Put the chicken shreds back in the pot, then add artichoke hearts, mozzarella, Parmesan, and cream (if you're using it). Cook while stirring occasionally until the cheeses are melted. Stir in spinach and garnish with parsley and more Parmesan. Serve.