Foryoueats: Quick Pastina Soup

Ingredients

• 1 tablespoon olive oil
• ½ cup minced celery (about 1 stalk, ends discarded)
• ½ cup minced carrot (about 1 carrot, ends discarded)
• ½ cup minced onion (about 1 small onion peeled and ends discarded)
• 1 quart reduced-sodium chicken broth
• 1 cup star pastina
• 1 cup frozen petite peas
• ½ cup grated Parmesan cheese
• 1 tablespoon fresh lemon zest (optional)
• salt and pepper to taste (optional)