Bennigan's Kilkenny Chicken Salad Recipe: Herb-Infused Mayo and Toasted Walnut Crunch

Bennigan's Kilkenny Chicken Salad delivers that signature restaurant flavor at home with its creamy herb-infused dressing and satisfying crunch. The secret lies in perfectly grilled chicken breast, toasted walnuts for texture, and a mayo base packed with fresh herbs and Dijon mustard.

I've recreated this dish countless times for my team at The Smoky Pig, and it never fails to impress.

This recipe starts with chicken breast marinated in buttermilk and herbs, then grilled to juicy perfection. The dressing combines mayo with fresh parsley, chives, and a touch of Dijon for brightness, while toasted walnuts add that signature crunch.

Every element comes together in a salad that's rich, flavorful, and packed with texture—just like the original.

What sets this version apart is the balance of creamy dressing and crisp components. The chicken stays tender and flavorful, the walnuts maintain their crunch even after toasting, and the herb dressing remains fresh-tasting. It's the kind of salad that satisfies cravings while feeling special enough for company.

Perfect for lunch meetings, picnic spreads, or a hearty weeknight dinner. The recipe scales easily for crowds while keeping all the restaurant-quality details. Let's recreate this classic at home with professional results.

Ingredients for bennigan's kilkenny chicken salad

These 14 ingredients bring Bennigan's signature chicken salad to life with restaurant-quality texture and flavor.

The chicken breast is the foundation—look for evenly sized pieces at the grocery store's butcher counter. Trader Joe's and Whole Foods carry pre-pounded chicken that saves time. For the herbs, freshness matters most—parsley and chives should be vibrant, not wilted. Walnuts are best bought in bulk; Costco offers great prices for the toasted variety, though you can toast them yourself at home. The Dijon mustard is non-negotiable for that signature tang—Amora or Maille brands deliver consistent quality. For the mayo, Hellmann's or Duke's are reliable choices, but any full-fat mayo works.

No buttermilk? Substitute milk with 1 tbsp lemon juice—it mimics the tang perfectly. Short on parsley? Fresh cilantro or dill at half the amount adds a different but pleasant brightness. Walnuts too expensive? Pecans or almonds work equally well when toasted. The chicken marinade can be prepped a day ahead, but the dressing is best made fresh to keep the herbs vibrant. For the lettuce, romaine holds up better than iceberg—it won't get soggy from the creamy dressing. Red bell pepper adds color and crunch; yellow or orange work too if that's what's available.

Marinated chicken keeps 2 days in the fridge, while the dressing stays fresh for 3 days if stored in an airtight container. Toasted walnuts maintain their crunch for 1 week in a sealed bag. For meal prep, assemble the salad just before serving to preserve texture. The dressing can be doubled and stored separately for up to 5 days—perfect for quick lunches. Walnuts can be toasted in bulk and frozen for 3 months to use as needed.

Step-by-step instructions for Bennigan's Kilkenny chicken salad

Here's the proven method for creating Bennigan's signature herb-infused chicken salad with perfect texture and flavor.

Place the 1.5 lb boneless, skinless chicken breast between two sheets of plastic wrap. Using a meat mallet, pound it to an even ½-inch thickness—this ensures even cooking. In a bowl, whisk together 1 cup buttermilk, 1 tbsp Dijon mustard, 1 tbsp lemon juice, 2 minced garlic cloves, 1.5 tsp salt, and 0.5 tsp black pepper. Pour the marinade over the chicken, ensuring full coverage, then refrigerate for at least 4 hours or overnight.

This step is crucial for tenderizing the chicken and infusing it with bright, herby flavors. The buttermilk creates a tenderizing effect while the acidity from the lemon juice helps break down proteins. Don't skip the marinating time—it makes all the difference in texture and flavor.

Preheat your grill to medium-high heat (about 375°F). Remove the chicken from the marinade (discard any excess) and grill for 5-6 minutes per side until the internal temperature reaches 165°F. Brush the chicken with 2 tbsp olive oil during the last minute of grilling to enhance browning. Let the chicken rest for 10 minutes before slicing into ¼-inch thick strips—this resting period keeps the meat juicy.

Watch the grill carefully—you want the chicken to develop a light char while remaining juicy inside. Overcooking will dry it out, so use a meat thermometer to check doneness. The slices should be tender enough to eat with a fork but still hold their shape when tossed with the salad ingredients.

In a dry skillet over medium heat, toast the 1.5 cups walnuts for 5-6 minutes, stirring constantly, until they're golden brown and fragrant. Remove from heat and set aside to cool. In a separate bowl, combine 1 cup mayonnaise, 0.5 cup chopped fresh parsley, and 0.25 cup chopped fresh chives. Mix well to create the herb-infused dressing.

The toasted walnuts should smell rich and nutty—this is your signal they're done. The dressing should be smooth with visible herb flecks throughout. If you prefer a lighter texture, you can blend the herbs into the mayo for a more uniform consistency, but I like the rustic look of visible herbs.

In a large bowl, combine the sliced grilled chicken, toasted walnuts, herb-infused dressing, 1 head chopped romaine lettuce, and 1 whole red bell pepper sliced into thin strips. Gently toss everything together until fully coated with the dressing. Taste and adjust seasoning if needed—you might want to add a pinch more salt or a squeeze of lemon juice to brighten the flavors.

The salad should have a vibrant mix of colors with tender chicken, crisp walnuts, and fresh vegetables. The dressing should coat everything evenly without making the salad soggy. This is where all the flavors come together—don't rush this step. The perfect Kilkenny chicken salad should be creamy, crunchy, and bursting with herbaceous notes.

Cover the salad and refrigerate for at least 1 hour before serving. This chilling time allows all the flavors to meld together beautifully. Serve on a bed of fresh lettuce or in a bowl with additional chopped herbs on top. The salad keeps well in the refrigerator for 2-3 days, making it perfect for meal prep.

When ready to serve, give the salad a final toss to redistribute the dressing. The chicken should be tender, the walnuts crunchy, and the herbs bright. Each bite should deliver a perfect balance of creamy, crunchy, and herby flavors that make this salad a standout dish.

Common mistakes when making great bennigan's kilkenny chicken salad

Overcooked Chicken

I can't stress enough how easy it is to overcook chicken breast—especially when grilling. The moment your chicken hits 165°F internal temperature, remove it immediately. I've seen many home cooks walk away from the grill only to return to dry, rubbery chicken.

Use a meat thermometer—it's the only foolproof way to avoid this mistake. 🌡️

Uneven Pounding

Skipping the even pounding step leads to unevenly cooked chicken. If your chicken breast is thicker in some spots, those areas will stay undercooked while the thinner parts dry out. Use a rolling pin or meat mallet to pound to a consistent ½-inch thickness throughout.

I like to wrap the chicken in plastic wrap first to make this step cleaner and more effective.

Skipping the Rest

You might be eager to serve that juicy-looking chicken immediately, but resisting this urge is crucial. Letting the chicken rest for 10 minutes after grilling allows the juices to redistribute. Cutting into it too soon causes all those precious juices to spill out, leaving you with dry chicken.

Trust me, this is one of those "no big deal" steps that makes a huge difference.

Dressing Too Thick

The herb dressing should be smooth but not gluey. If you're using store-bought mayo, check the consistency first—some brands are thicker than others. I've seen people struggle with dressing that's too thick to coat the salad properly.

If needed, add 1 tsp lemon juice or water to thin it out. The dressing should coat a spoon easily without dripping.

Walnuts Burned

Watch those walnuts like a hawk! They go from perfect to burnt in seconds. Toast them over medium heat and stir constantly. I've had to toss batches because they turned bitter from overheating.

Remove them from heat the moment they're golden brown—they'll continue cooking from residual heat. Let them cool completely before adding to the salad to maintain their crunch.

Lettuce Too Wet

Romaine lettuce can get soggy when mixed with creamy dressing. To prevent this, I recommend chopping the lettuce just before assembling the salad. Also, pat dry any excess moisture from the lettuce leaves.

If your salad ends up too wet, add more walnuts or croutons to absorb the excess liquid. The texture should be balanced—creamy but not soggy, crunchy but not dry.

Frequently asked questions