In a pot, combine the chicken broth, onion, carrot, celery, and garlic (cut into large chunks). Simmer for 20 minutes until the vegetables are soft.

Add the star pasta and cook according to the package instructions.

Remove from heat. Add the egg yolk, butter, lemon juice, and zest while stirring constantly so the yolk doesn't curdle.

Serve hot with freshly ground pepper and a drizzle of olive oil.

Creamy egg-lemon soup with star pasta