This Fish Sandwich recipe stacks a flaky crispy fish fillet with creamy avocado, crisp lettuce, and a bright lemon-infused sauce on buttery toasted brioche buns. It’s big on flavor and ready in under 25 minutes.
author’s note
My Filet-O-Fish loving brother-in-law approved this one!
My brother-in-law is a big fan of McDonald’s Filet-O-Fish, so I wanted to make a fish sandwich he’d love at home. After testing, I realized you don’t need to bread and fry fish from scratch when good frozen fillets exist. I used a crispy frozen fillet as the base and focused on quick, tasty toppings.
Layered on buttery toasted brioche with sliced avocado, crunchy lettuce, pickles, and a lemony tartar-style sauce, these sandwiches were a hit. They’re quick to pull together and perfect for busy weeknights.
Fish Sandwich Ingredients:
| Ingredient | Swaps & Tips |
|---|---|
| Brioche buns | Potato or Hawaiian buns work well too. |
| Frozen crispy fish fillets | Use your favorite brand; air frying gives extra crispiness and is fast. |
| Avocado | Thinly sliced ripe avocado adds richness. If unavailable, a smear of store-bought guacamole works. |
| Lettuce | Butter, romaine, or shredded iceberg all work—make sure it’s dry to avoid sogginess. |
| Mayo | Full-fat mayo gives the best flavor for the sauce. |
| Lemon | Use both zest and juice for the sauce to add bright acidity. |
| Sweet pickle relish | Finely diced bread-and-butter pickles are a good substitute if you prefer. |
| Fresh dill | Dried dill can be used in a pinch—use a smaller amount. |
How To Make This Fish Sandwich
- Make the sauce: Whisk together the mayo, sweet pickle relish, finely chopped fresh dill (optional), Worcestershire sauce, Dijon-style mustard, lemon zest, lemon juice, and a pinch of salt and pepper. Chill while you prepare the rest.
- Cook the fish: Air fry or bake the frozen fish fillets according to package directions until golden and crisp.
- Toast the buns: Spread softened butter on the cut sides of the brioche buns and toast buttered-side down in a pan or on a griddle over medium heat until golden—watch carefully so they don’t burn.
- Assemble: Spread the sauce on both bun halves. Layer with lettuce, avocado slices, the hot crispy fish fillet, and pickles if using. Top with the other bun half.
- Serve immediately: These are best eaten hot so the fish stays crisp and the bread stays toasted.
chelsea’s recipe tip
My Top Fish Sandwich Tips
- Don’t overcrowd the air fryer or oven: Give fillets space so they crisp evenly.
- Always toast the buns: Toasting adds flavor and prevents the buns from getting soggy.
- Dry your lettuce: Excess moisture will make the sandwich soggy quickly.
- Let the sauce chill: It develops more flavor after a short rest in the fridge.
What To Serve With A Fish Sandwich
- Fries: Sweet potato fries or crispy air fryer fries pair well.
- Coleslaw: A cool, crunchy slaw complements the crispy fish.
- Fruit salad: A bright fruit salad balances the richness.
- Chips: Quick and easy for busy nights.
- Pasta salad: A chilled pasta salad makes this a great summer dinner.
Storage
This sandwich is best enjoyed fresh when the fish is still crispy. Store extra sauce in an airtight container in the refrigerator for 3–4 days. Reheat leftover fillets in the air fryer to help restore crispiness. Avoid assembling sandwiches far in advance to prevent sogginess.
More Easy Sandwich Recipes:
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Fish Sandwich
Ingredients
- 1/2 cup mayo (Best Foods/Hellman’s recommended)
- 1–1/2 tablespoons sweet pickle relish
- 1 tablespoon finely chopped fresh dill (optional)
- 1/2 teaspoon Worcestershire sauce
- 1/2 teaspoon Dijon-style mustard
- 1 lemon (zest and juice)
- 1/8 teaspoon salt and 1/8 teaspoon pepper
- 1 brioche bun, softened butter for toasting
- 1 frozen fish sandwich fillet (follow package instructions)
- 1/4 large ripe avocado, thinly sliced
- 2 pieces lettuce
- Pickles, optional
Instructions
- Combine all sauce ingredients in a medium bowl, including 1/2 teaspoon lemon zest and 2 tablespoons lemon juice. Season with salt and pepper to taste. Mix well and refrigerate until ready to use. Stir again before spreading.
- Cook the frozen fish fillet following package directions—air fry or bake until crispy and heated through.
- Spread softened butter on the inside of the brioche bun halves. Toast buttered sides down in a pan or on a griddle over medium heat for 30 seconds to 1 minute, or until golden. Watch closely to avoid burning.
- Spread the prepared sauce on both toasted bun halves. Layer lettuce, avocado slices, the hot fish fillet, and pickles if using. Top with the other bun half and serve immediately.
Recipe Notes
Note 2: Gorton’s fish sandwich fillets are a favorite, but any crispy frozen fillet will work. An air fryer makes them extra crisp and speeds cooking.
Nutrition: Values vary with butter amount, relish, and bun brand.
Storage: Best eaten fresh. Keep extra sauce refrigerated for 3–4 days and reheat fillets in the air fryer to regain crispiness.
Nutrition
Nutrition information is an approximation and will vary based on ingredients and portions.