Simmer the vegetables

• Add the chopped onion, carrots and celery to a pot with the chicken broth.
• Season with salt.
• Bring to a boil, then lower the heat and let simmer until the vegetables are very soft.

Blend the vegetables

• Transfer the cooked vegetables to a blender or food processor.
• Blend until smooth.
• Pour the puree back into the broth in the pot.

Cook the pasta

• Add the pastina to the soup and stir occasionally.
• Cook until the pasta is tender, then remove from the heat and let cool a little before serving.

Serve

• Ladle the soup into bowls.
• Top with grated parmesan cheese or croutons.