Crispy Onion Chicken Sandwich

Featured in: Weeknight Dinners

This mouthwatering sandwich combines tender, juicy fried chicken marinated in buttermilk with a delightful crunch from crispy fried onions. The creamy garlic aioli ties everything together beautifully, nestled in soft, toasted brioche buns. With just 50 minutes from start to finish, this American classic serves four and delivers restaurant-quality results at home. Perfect for lunch or dinner.

Updated on Sun, 18 Jan 2026 13:25:00 GMT
Golden-brown Crispy Onion Chicken Sandwich stacked high on a plate, with fried chicken thighs, crunchy fried onions, and creamy aioli on a toasted brioche bun. Save
Golden-brown Crispy Onion Chicken Sandwich stacked high on a plate, with fried chicken thighs, crunchy fried onions, and creamy aioli on a toasted brioche bun. | stellarcrust.com

My neighbor knocked on my door one Sunday holding a paper bag stained with grease and said, Try this before you say no to anything today. Inside was a fried chicken sandwich so good I forgot I was still in my pajamas. The crunch of those onions against the tender chicken stuck with me for weeks until I finally cornered her for the recipe. She laughed and said it was just throwing things together, but I knew better. That sandwich had technique written all over it.

I made this for a backyard gathering last summer, and three people asked if I'd cater their next party. One friend stood by the kitchen counter eating his second sandwich in silence, occasionally pointing at it and nodding. My sister declared it better than the spot downtown that charges fifteen dollars and makes you wait an hour. I realized then that some recipes earn their place not by being fancy, but by being so satisfying they quiet a room.

Ingredients

  • Boneless, skinless chicken thighs: Thighs stay juicier than breasts and handle frying like champions, soaking up the marinade and crisping beautifully without drying out.
  • Buttermilk: The acidity tenderizes the meat while adding a subtle tang that makes the chicken taste like it came from a diner that knows what it's doing.
  • Garlic powder and paprika: These give the marinade a gentle warmth and depth without overpowering the chicken's natural flavor.
  • All-purpose flour and cornstarch: The combination creates a lighter, crispier crust than flour alone, with cornstarch adding that audible crunch.
  • Smoked paprika: A little smokiness in the breading makes the fried coating taste more complex, like it has a secret.
  • Yellow onion: Thinly sliced and fried, these turn into golden, crispy strands that add sweetness and texture to every bite.
  • Mayonnaise: The base of the aioli, it brings richness and creaminess that balances the crispy, savory elements.
  • Garlic clove and lemon juice: Fresh garlic and a squeeze of lemon brighten the aioli, cutting through the richness and waking up your taste buds.
  • Dijon mustard: Just a touch adds a subtle sharpness that makes the aioli more interesting than plain mayo ever could.
  • Brioche buns: Soft, slightly sweet, and sturdy enough to hold everything without falling apart, they make the sandwich feel special.

Instructions

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Marinate the chicken:
Whisk together buttermilk, garlic powder, paprika, salt, and black pepper in a bowl, then add the chicken thighs and turn them until every inch is coated. Cover and refrigerate for at least 30 minutes, though a few hours makes them even more tender and flavorful.
Prepare the breading:
In a shallow dish, combine flour, cornstarch, smoked paprika, salt, and black pepper, mixing until the spices are evenly distributed. This dry mixture will become the crispy shell that makes the chicken irresistible.
Coat the onions:
Toss thinly sliced onions with flour, salt, and black pepper in a separate bowl, making sure each strand is lightly dusted. They'll fry up into golden, crunchy tangles that add sweetness and crunch.
Fry the onions:
Heat about an inch of vegetable oil in a large skillet to 350°F, then fry the onions in small batches for 2 to 3 minutes until golden and crisp. Drain them on paper towels and try not to eat them all before assembly.
Bread the chicken:
Pull each thigh from the marinade, letting excess buttermilk drip off, then press it firmly into the breading mixture on both sides. The key is to really press so the coating sticks and crisps up beautifully.
Fry the chicken:
Gently lower the breaded thighs into the hot oil and fry for 5 to 7 minutes per side until deeply golden and cooked through. Transfer them to a wire rack so they stay crispy instead of steaming on a plate.
Make the aioli:
Stir together mayonnaise, minced garlic, lemon juice, Dijon mustard, salt, and pepper in a small bowl until smooth and creamy. Taste and adjust seasoning, adding more lemon if you want extra brightness.
Toast the buns:
Butter the cut sides of the brioche buns and toast them in a skillet until golden and fragrant. This step is optional, but it adds a buttery crunch that makes the sandwich feel even more complete.
Assemble the sandwiches:
Spread aioli generously on both sides of each bun, then layer with lettuce if using, a fried chicken thigh, and a big mound of crispy onions. Press the top bun gently and get ready for something special.
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Keeps spices within easy reach while cooking, helping you season dishes quickly during everyday meal prep.
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Freshly made Crispy Onion Chicken Sandwich on a wooden board, revealing juicy buttermilk-marinated chicken, a layer of crispy onions, and lettuce on a soft bun. Save
Freshly made Crispy Onion Chicken Sandwich on a wooden board, revealing juicy buttermilk-marinated chicken, a layer of crispy onions, and lettuce on a soft bun. | stellarcrust.com

The first time I served this at a casual dinner, my friend who claims she doesn't like fried food took one bite and went silent. Then she looked at me and said, Okay, I like this fried food. We ended up sitting on the porch with sandwiches in hand, talking until the sun went down. It's funny how a really good sandwich can turn a regular evening into a memory you keep coming back to.

What Makes the Chicken So Tender

The buttermilk marinade isn't just for flavor, it's doing real work behind the scenes. The acidity breaks down the proteins in the chicken, turning even basic thighs into something incredibly tender and juicy. I used to think marinating was optional, something you did if you had extra time, but after tasting the difference I never skip it anymore. Even 30 minutes makes a noticeable change, and if you can give it a few hours, the chicken practically melts under that crispy crust. It's one of those small steps that separates good fried chicken from the kind people remember.

Getting the Onions Perfectly Crispy

The secret to crispy onions is slicing them thin and frying them fast in small batches. If you overload the pan, the temperature drops and they turn limp and greasy instead of golden and crunchy. I learned this the hard way when I dumped half an onion in at once and ended up with sad, soggy strands. Now I take my time, frying just a handful at a time and watching them turn from pale to golden in less than three minutes. They cool quickly and stay crispy for a while, so you can make them ahead and have them ready when the chicken comes out of the oil.

Serving Suggestions and Variations

This sandwich is fantastic on its own, but a few simple sides can turn it into a full meal. I like serving it with dill pickles for a tangy crunch, or a quick cabbage slaw with a vinegar based dressing to cut through the richness. Sweet potato fries or regular fries work beautifully alongside, and if you want to lean into comfort food territory, add a cold beer or a fizzy lemonade. For a spicier version, stir hot sauce into the aioli or add cayenne to the breading. You can also swap chicken thighs for breasts if that's what you prefer, just adjust the cooking time since breasts cook a bit faster.

  • Add pickles or coleslaw for a tangy, crunchy contrast that balances the richness.
  • Try hot sauce in the aioli or cayenne in the breading if you like a little heat.
  • Swap chicken thighs for breasts if you prefer, just watch the cooking time closely.
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Plated Crispy Onion Chicken Sandwich with golden fried chicken and crispy onions, served beside a small bowl of aioli and pickles for dipping. Save
Plated Crispy Onion Chicken Sandwich with golden fried chicken and crispy onions, served beside a small bowl of aioli and pickles for dipping. | stellarcrust.com

This sandwich has become my go to when I want to impress someone without pretending I'm a chef. It's messy, satisfying, and tastes like you spent all day in the kitchen even though it comes together in under an hour.

Recipe FAQs

How long should I marinate the chicken?

Marinate the chicken for at least 30 minutes, though 2-4 hours yields deeper flavor and more tender results. You can prepare the marinade the night before for convenience.

Can I use chicken breasts instead of thighs?

Yes, chicken breasts work well as a substitute. They cook faster, typically 3-5 minutes per side. Pound them to even thickness for uniform cooking and moisture retention.

What's the best way to keep the fried onions crispy?

Fry the onions just before serving and drain them thoroughly on paper towels. Store them in an airtight container for up to 2 hours. Add them to the sandwich right before eating to maintain maximum crunch.

How can I make the aioli less garlicky?

Reduce the garlic to half a clove and increase the mayonnaise slightly. You can also roast the garlic clove first to mellow its sharpness, or substitute with garlic powder for gentler flavor.

What temperature should the oil be for frying?

Maintain oil at 350°F (175°C) for both onions and chicken. Use a thermometer to monitor temperature. If too hot, the coating burns; if too cool, the food becomes greasy rather than crispy.

What sides pair well with this sandwich?

Pickles, coleslaw, or fresh slaw add excellent crunch and acidity to balance the richness. Fries, chips, or a light salad also complement the sandwich beautifully.

Crispy Onion Chicken Sandwich

Buttermilk-marinated fried chicken topped with crispy onions and garlic aioli on toasted brioche buns.

Time to Prep
25 minutes
Time to Cook
25 minutes
Overall Time
50 minutes
Recipe by Logan Smith


Skill Level Medium

Cuisine American

Makes 4 Portions

Diet Preferences None specified

What You'll Need

Chicken & Marinade

01 4 boneless, skinless chicken thighs
02 1 cup buttermilk
03 1 teaspoon garlic powder
04 1 teaspoon paprika
05 1/2 teaspoon salt
06 1/2 teaspoon black pepper

Breading

01 1 cup all-purpose flour
02 1/2 cup cornstarch
03 1 teaspoon smoked paprika
04 1 teaspoon salt
05 1/2 teaspoon ground black pepper

Crispy Onions

01 1 large yellow onion, thinly sliced
02 1/2 cup all-purpose flour
03 1/2 teaspoon salt
04 1/2 teaspoon black pepper
05 Vegetable oil for frying

Aioli

01 1/2 cup mayonnaise
02 1 large garlic clove, minced
03 1 tablespoon fresh lemon juice
04 1/2 teaspoon Dijon mustard
05 Salt and black pepper to taste

Assembly

01 4 brioche buns, sliced
02 Butter for toasting buns, optional
03 Lettuce leaves, optional

How to Make It

Step 01

Prepare Buttermilk Marinade: In a mixing bowl, whisk together buttermilk, garlic powder, paprika, salt, and black pepper. Submerge chicken thighs ensuring complete coating. Cover and refrigerate for minimum 30 minutes or up to 4 hours.

Step 02

Mix Breading Mixture: In a shallow dish, combine flour, cornstarch, smoked paprika, salt, and black pepper. Set aside for dredging.

Step 03

Coat Onion Slices: In a separate bowl, toss sliced onions with flour, salt, and black pepper until evenly coated.

Step 04

Fry Onions: Heat 1 inch of vegetable oil in a large skillet to 350°F. Working in batches, fry onions for 2-3 minutes per batch until golden and crispy. Transfer to paper towels for drainage.

Step 05

Dredge Chicken: Remove marinated chicken from refrigerator, allowing excess buttermilk to drip off. Dredge each thigh thoroughly in breading mixture, pressing gently to ensure adhesion.

Step 06

Fry Chicken: Fry breaded chicken thighs in the same hot oil for 5-7 minutes per side until golden brown and cooked through internally. Transfer to wire rack or paper towels to drain excess oil.

Step 07

Prepare Aioli: In a small bowl, combine mayonnaise, minced garlic, lemon juice, Dijon mustard, salt, and pepper. Mix until smooth and well incorporated.

Step 08

Toast Brioche Buns: Optional step: Butter brioche buns and toast in skillet until light golden brown on cut sides.

Step 09

Assemble Sandwiches: Spread aioli on both cut sides of each bun. Layer with optional lettuce, fried chicken thigh, generous portion of crispy onions, and top with bun. Serve immediately.

Tools You Need

  • Mixing bowls
  • Large skillet or deep fryer
  • Kitchen tongs
  • Wire rack or paper towels
  • Sharp knife and cutting board

Allergy Info

Always review each ingredient for allergens, and ask a healthcare provider if you’re unsure.
  • Contains eggs in mayonnaise
  • Contains wheat in all-purpose flour and brioche buns
  • Contains milk in buttermilk and butter
  • Contains mustard in aioli
  • Brioche buns may contain soy or additional allergens; verify packaging before consumption

Nutrition Info (per portion)

This nutrition information serves as a guideline. For health concerns, talk to a professional.
  • Energy: 670
  • Total Fat: 32 g
  • Carbohydrates: 61 g
  • Proteins: 32 g