Soothing Italian Penicillin Soup (Pastina in Brodo)
Italian Penicillin Soup is the bowl of comfort you reach for when you need something warm, nourishing, and easy to make. It’s a simple pastina soup made with tiny pasta, rich chicken broth, a gentle swirl of egg, and plenty of Parmesan.
There’s no heavy cream or complicated steps here, just a clean, savory broth that tastes like the kind your mom might have made. The lemon brightens everything at the end, and the silky egg strands make each spoonful feel extra restorative.
What Makes This Soup So Comforting
The combination of salty Parmesan, tender pastina, and a very light egg-drop effect gives this soup a texture that’s both gentle and satisfying. It’s the kind of meal you can make in about half an hour, and it never feels heavy.
I always keep a container of pastina in the pantry and a chunk of Parmesan rind in the freezer just for this soup. It’s my go-to when someone is sick, or when the weather turns cold.
Ingredients
- 2 tbsp olive oil: just enough to soften the vegetables.
- 1 small yellow onion, finely diced: keeps the broth smooth, no big chunks.
- 2 medium carrots, peeled and finely diced: adds a little sweetness.
- 2 celery stalks, finely diced: for that classic base flavor.
- 2 garlic cloves, minced: don’t overdo it, you want a gentle hum.
- 8 cups good-quality chicken broth: homemade if you have it, otherwise a low-sodium store-bought brand.
- 1 small Parmesan rind: (optional but worth it): it adds a savory depth you can’t get from grated cheese alone.
- 1 cup pastina: (such as stelline or acini di pepe): the tiny star-shaped pasta that makes this soup.
- 2 large eggs: they create the silky strands.
- ½ cup freshly grated Parmesan cheese, plus more for serving.
- 1 to 2 tbsp fresh lemon juice: start with 1 and adjust, it should brighten not sour.
- Salt and freshly ground black pepper.
- 2 tbsp chopped fresh parsley: for a fresh finish.
Variations / Substitutions
- Swap the pastina: orzo, ditalini, or even cooked tortellini work well. Cook time will change a bit.
- Add shredded cooked chicken: if you have leftover roast chicken, stir it in at the end.
- Skip the egg: the soup is still wonderful as a simple pastina in brodo. Use extra Parmesan to keep it rich.
- Make it vegetarian: use a rich vegetable broth and add extra carrot and celery, plus a little nutritional yeast for savory depth.
- Herb swap: fresh dill or chives work in place of parsley.
Classic Grinder Sandwich is a great main dish to serve alongside this soup.
How to Make Italian Penicillin Soup
Step 1: Sauté the Vegetables
Heat the 2 tbsp olive oil in a large pot or Dutch oven over medium heat. Add the onion, carrots, and celery with a pinch of salt. Cook, stirring occasionally, for about 6 to 8 minutes, until the vegetables have softened and the onion is translucent.
Then add the garlic and cook for 1 more minute, just until it smells fragrant. You don’t want any color on the garlic, so keep the heat moderate.
Step 2: Simmer the Broth and Pastina
Pour in the 8 cups chicken broth and add the Parmesan rind if using. Bring the soup to a boil over high heat, then add the 1 cup pastina. Reduce the heat to a gentle simmer and cook for about 8 minutes, or until the pasta is tender but still has a little bite. Stir every few minutes so the tiny stars don’t stick to the bottom of the pot.
The broth will start to get slightly cloudy from the starch the pastina releases. That’s exactly what you want, it gives the soup a little more body.
Step 3: Whisk and Temper the Egg Mixture
While the soup simmers, whisk together the 2 eggs, ½ cup grated Parmesan, and 1 tablespoon of the lemon juice in a medium bowl until smooth. When the pasta is cooked, turn the heat to the lowest possible setting. Very slowly drizzle the egg mixture into the hot soup, stirring the soup constantly in one direction with a fork. You’ll see thin, silky white strands form instantly.
Tempering the eggs this way keeps them from scrambling into curds, so make sure the soup is not boiling when you add the egg. The residual heat is enough to cook the egg gently into ribbons.
Step 4: Ladle and Serve
Taste the soup and add more salt, pepper, or lemon juice as needed. Remove the Parmesan rind if you used it and stir in most of the chopped parsley. Ladle the soup into bowls and top each serving with a little extra grated Parmesan and the remaining parsley. Serve right away, while the pastina still has some texture and the broth is piping hot.
Tips for the Best Bowl of Soup
- Use a really good broth.: Since the broth is the backbone, choose one you love. If using store-bought, a low-sodium version lets you control the salt and keeps the Parmesan from making it too salty.
- Don’t overcook the pastina.: It will continue to absorb liquid and soften even after you turn off the heat, so cook it just until al dente. If you plan on leftovers, cook the pastina separately and add it to each bowl.
- Temper carefully.: The key to beautiful egg strands is low heat and constant stirring when you drizzle in the egg mixture. If your broth is bubbling, the eggs will turn into scrambled bits.
- Parmesan rind magic.: It’s optional, but that rind adds a savory, nutty depth that plain broth can’t match. I stash rinds in a bag in the freezer and toss one into soups and sauces all the time.
Storing Leftover Soup
- Refrigerate: Store any leftover soup in an airtight container for up to 3 days. The pastina will swell and the soup will thicken; thin it with a splash of broth or water when you reheat it.
- Reheating: Warm the soup gently on the stove over medium-low heat, stirring occasionally. A fresh squeeze of lemon right before serving helps perk up the flavors.
Frequently Asked Questions
Can I use a different pasta shape?
Absolutely, any small shape like orzo, ditalini, or even broken spaghetti works. Adjust the cooking time to the package instructions, and keep in mind that larger pasta will make the soup a bit heartier.
Can I make this soup vegetarian?
Yes, swap the chicken broth for a good vegetable broth and omit the Parmesan rind. You’ll want to add a little nutritional yeast or extra grated Parmesan to boost the savory flavor. The egg mixture stays the same.
Why did my eggs scramble?
That happens if the broth is too hot or you pour the egg mixture too fast. Keep the soup at a bare simmer, not boiling, and stir quickly and steadily as you drizzle.
Can I freeze this soup?
You can, but the pastina texture will soften significantly after thawing. It’s better to freeze the broth and vegetable base separately, and then cook fresh pastina in it when you reheat.
Italian Penicillin Soup Recipe
Ingredients
Method
- Heat the olive oil in a large pot over medium heat. Add the onion, carrots, and celery with a pinch of salt. Cook, stirring occasionally, until softened, about 6 to 8 minutes. Add the garlic and cook 1 more minute.
- Pour in the chicken broth and add the Parmesan rind if using. Bring to a boil, then add the pastina. Reduce the heat to a simmer and cook until the pasta is just tender, about 8 minutes, stirring occasionally.
- While the soup simmers, whisk together the eggs, ½ cup Parmesan, and 1 tablespoon of the lemon juice. Turn the heat under the soup to the lowest setting. Slowly drizzle the egg mixture into the hot soup, stirring constantly with a fork, until thin strands form.
- Season to taste with salt, pepper, and more lemon juice. Remove the Parmesan rind. Stir in most of the parsley, then ladle the soup into bowls and top with extra Parmesan and the remaining parsley. Serve immediately.
Notes
