01 -
Bring the broth, onion, carrots, celery, garlic, and salt to a boil in a large Dutch oven or saucepan. Reduce heat to medium-low and simmer until the vegetables are softened, about 10 minutes.
02 -
Using a slotted spoon, transfer the cooked vegetables and 1 cup of the broth to a blender. Puree until smooth, then stir the mixture back into the pot.
03 -
Add the thyme sprigs, bay leaves, and Parmesan rind. Return the soup to a gentle boil over medium-high heat.
04 -
Add the pastina and simmer, stirring occasionally, until the pasta is tender, 18 to 20 minutes. Stir in the shredded chicken during the last 3 minutes to heat through.
05 -
Remove and discard the thyme, bay leaves, and Parmesan rind. Ladle into bowls and garnish with parsley and grated Parmesan.