Italian Penicillin Soup with Chicken: Cozy Pastina Recipe

Italian penicillin soup is a cozy Italian-American-style chicken soup made with tender chicken, vegetables, broth, and tiny pastina pasta. The nickname is informal, not a medical claim; the appeal is a savory, gently lemony bowl that comes together in one pot and suits a cold evening or a simple family dinner.

Ingredients

2 tablespoons (30 ml) olive oil
1 medium yellow onion, finely diced, about 1 cup (150 g)
2 medium carrots, peeled and diced, about 1 cup (160 g)
2 celery ribs, diced, about ¾ cup (80 g)
3 garlic cloves, finely minced, about 1 tablespoon (9 g)
1¼ pounds (570 g) boneless, skinless chicken breasts
8 cups (1.9 L) low-sodium chicken broth
1 dried bay leaf (about 0.2 g)
½ teaspoon (1 g) dried thyme
1 Parmesan rind, about 1 ounce (28 g), optional
1 teaspoon (6 g) fine salt, plus more to taste
¼ teaspoon (0.5 g) freshly ground black pepper
1 cup (160 g) pastina, such as stelline or acini di pepe
½ cup (45 g) finely grated Parmesan cheese, plus extra for serving
1 tablespoon (15 ml) fresh lemon juice, or more to taste
2 tablespoons (8 g) chopped fresh parsley

Pastina means tiny pasta, and the exact shape varies by brand and family preference. Stelline, acini di pepe, orzo, and small ditalini all work; use the package cooking time because shapes and sizes differ. If pastina is hard to find, broken spaghetti or another small pasta is a practical substitute, though the soup will have a less delicate texture. A Parmesan rind adds savory depth but is optional; omit it if unavailable, and finish with a little extra grated cheese instead.

Instructions

Prepare the vegetables. Dice the onion, carrots, and celery into small, even pieces so they soften at about the same rate. Mince the garlic and set the vegetables near the stove. Pat the chicken dry with paper towels. Keeping the pieces of vegetable small gives the broth a pleasant texture and makes each spoonful easy to eat.
Soften the aromatics. Heat the olive oil in a large, heavy soup pot or Dutch oven over medium heat. Add the onion, carrots, celery, salt, and pepper. Cook for about 8 minutes, stirring every minute or two, until the onion is translucent and the carrots have started to soften. Add the garlic and thyme and stir for 30 seconds, just until fragrant; do not let the garlic brown.
Simmer the chicken. Pour in the chicken broth and add the bay leaf and Parmesan rind, if using. Nestle the chicken breasts into the broth. Bring the pot to a gentle boil, then reduce the heat so the liquid simmers steadily rather than bubbling hard. Cover partially and cook for about 20 minutes, turning the chicken once if it is not fully submerged. Check the thickest part of each breast with a food thermometer: USDA FSIS guidance sets the safe minimum internal temperature for poultry at 165°F (74°C). If a piece has not reached that temperature, keep simmering and check again after a few minutes.
Shred the chicken. Use tongs to transfer the cooked chicken to a clean plate or cutting board. Let it rest just long enough to handle, then shred it with two forks or cut it into small bite-size pieces. Remove and discard the bay leaf and Parmesan rind. Keep the pot at a gentle simmer while you prepare the pasta; avoid boiling the broth vigorously, which can make it cloudy and reduce it too quickly.
Cook the pastina in the soup. Stir the pastina into the simmering broth and cook according to its package directions, usually about 6 to 8 minutes, stirring frequently so the small pasta does not stick to the bottom. Taste a piece near the end; it should be tender but not mushy. If the broth has reduced more than you like, add ½ cup (120 ml) hot water or broth and bring it back to a simmer.
Finish and season. Return the shredded chicken to the pot and stir in the grated Parmesan and lemon juice. Warm for 1 to 2 minutes, just until the chicken is hot and the cheese has melted into the broth. Taste before adding more salt, since Parmesan and prepared broth can already be salty. Stir in the parsley, then ladle the soup into warm bowls with extra Parmesan and black pepper at the table.

The listed cooking time assumes average-size chicken breasts and pastina that cooks in under 10 minutes. Very thick chicken may need extra simmering to reach the safe temperature, and some pasta shapes take longer than others. Use the thermometer and the pasta package directions rather than relying on the clock alone.

Tips

Choose broth with room for seasoning. Low-sodium broth makes it easier to control the final salt level, especially when adding Parmesan. If you have regular salted broth, start with less added salt and adjust only after the cheese and lemon go in.
Cut the vegetables evenly. Pieces around ¼ inch (6 mm) soften quickly and distribute well through the soup. Larger chunks are fine if you prefer a heartier texture, but give them a few extra minutes in the pot before adding the broth.
Keep the simmer gentle. A rolling boil can toughen chicken and break up the vegetables. Gentle bubbles are enough to cook the chicken safely; the thermometer reading, not the appearance of the broth, confirms it has reached 165°F (74°C).
Expect pastina to absorb broth. The soup thickens as it stands because the pasta continues to take up liquid. If you want leftovers to stay brothy, cook the pastina separately and add it to bowls, or loosen reheated soup with a splash of broth or water.

Serving Suggestions

Serve the soup hot in shallow bowls, with grated Parmesan, chopped parsley, and a little extra lemon available for each person to add. Crusty bread, garlic toast, or warm focaccia makes an easy accompaniment for dipping into the broth. For a simple meal with more vegetables, add a crisp green salad dressed with olive oil and vinegar; keep the salad bright and lightly dressed so it does not compete with the rich, savory soup.

This recipe is filling enough to serve as a main course, especially when each bowl gets a generous portion of chicken and pastina. If serving it as a first course, use smaller bowls and follow it with roasted vegetables or a straightforward pasta dish. Put extra Parmesan on the table rather than stirring a large amount into the whole pot, so diners can choose how cheesy they want their serving.

Variations

Use chicken thighs: Boneless, skinless thighs can replace the breasts in the same weight. They may take a little longer to cook, so check the thickest piece with a thermometer and remove the chicken only after it reaches 165°F (74°C). Their texture is a little richer and more tender.

Add greens: Stir in 2 packed cups (about 60 g) baby spinach during the last minute of cooking, or add 1 cup (about 30 g) chopped kale with the broth so it has time to soften. Spinach wilts quickly; kale stays more substantial. These are flexible additions, not required ingredients.

Make it more lemony: Add another teaspoon or two of lemon juice after tasting, or serve lemon wedges alongside the bowls. A small amount brightens the broth; add it gradually so the soup remains savory rather than sharply sour.

Adjust the pasta: Use orzo, acini di pepe, stelline, or ditalini in place of the listed pastina, measuring 1 cup (about 160 g) and following the package timing. For gluten-free soup, choose a small gluten-free pasta and cook it separately if it tends to shed starch or soften quickly; check that the broth and any packaged ingredients are also labeled gluten-free.

Storage and Reheating

Cool leftovers promptly and refrigerate them within 2 hours in shallow, airtight containers. The soup keeps for 3 to 4 days in the refrigerator. The pastina will continue absorbing broth, so the texture becomes thicker by the next day; add a little water or chicken broth when reheating to restore a spoonable consistency.

Reheat only the portion you plan to serve in a saucepan over medium-low heat, stirring occasionally until it is steaming throughout. Check that leftovers reach 165°F (74°C), the USDA FSIS safe reheating temperature. Add a splash of broth if needed, then taste and refresh with Parmesan, parsley, or a few drops of lemon. You can also microwave a serving in a covered microwave-safe bowl, stirring partway through and checking the temperature in more than one spot.

For longer storage, freeze the soup for up to 2 months in freezer-safe containers, leaving a little room for expansion. The pasta may become softer after thawing, so for the best texture freeze the chicken and broth without pastina, then cook fresh pasta when you reheat it. Thaw frozen soup overnight in the refrigerator or reheat it from frozen over low heat, stirring as it loosens; bring it to 165°F (74°C) before serving.

Frequently Asked Questions

Why is it called Italian penicillin soup?

Italian penicillin is an informal nickname for a comforting chicken soup, especially versions with tiny pasta. It is not a medical treatment, and the name does not indicate that the soup prevents or cures illness. This version focuses on the familiar combination of chicken, vegetables, broth, Parmesan, and pastina.

Can I use cooked or rotisserie chicken?

Yes. Skip simmering raw chicken and add about 3 cups (420 g) shredded cooked chicken when the pastina has finished cooking. Warm it through for a few minutes, then add Parmesan and lemon. Because cooked chicken can vary in saltiness, taste the broth before adding the full amount of salt.

Can I make the soup without Parmesan rind?

Absolutely. The rind contributes a deeper, savory flavor as it simmers, but the soup still works without it. Finish with the grated Parmesan listed in the ingredients, or leave out the cheese for a dairy-free bowl. The broth will taste a little less rich, so take care to season it well with salt, pepper, and lemon.

Should I cook the pastina in the soup or separately?

Cooking it directly in the broth is convenient and lets the pasta take on the soup’s flavor, but it thickens the pot as it absorbs liquid. Cooking it separately is useful if you expect leftovers or want to control the texture: divide cooked pasta among bowls and ladle the chicken soup over it. Keep any separately stored pasta chilled and use it within 3 to 4 days.

What can I use if I cannot find pastina?

Choose another small pasta such as acini di pepe, orzo, stelline, or ditalini. Broken thin spaghetti is another practical option; snap it into short pieces before cooking. Since pasta shapes have different cooking times, check the package and taste for tenderness rather than assuming every substitute will be ready in the same number of minutes.

Can I make this soup ahead?

Yes. For the best texture, prepare the chicken and broth a day ahead, chill them promptly, and cook the pastina shortly before serving. Reheat the soup base until it reaches 165°F (74°C), then simmer the pasta in it or add separately cooked pasta. If the pasta is already in the pot, expect the stored soup to be thicker and loosen it with broth as you warm it.

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Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes

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