- 1 English cucumber, thinly sliced
- ½ red bell pepper, chopped
- ¼ small red onion, finely chopped
- 1 tablespoon chopped parsley
- 2 tablespoons lemon juice, plus wedges for serving
- ¼ cup olive oil
- Kosher salt and black pepper
- 4 thin 4-ounce skinless bass or cod fillets
- 3 tablespoons all-purpose flour
- Tartar sauce, toasted burger buns, and Bibb lettuce, for serving
- Toss the cucumber, bell pepper, onion, parsley, lemon juice, 2 tablespoons of the olive oil, ½ teaspoon salt, and ¼ teaspoon black pepper in a medium bowl. Let sit for about 15 minutes.
- Meanwhile, season the fish with 1 teaspoon salt and ½ teaspoon black pepper. Coat with the flour.
- Heat the remaining 2 tablespoons of oil in a large nonstick skillet over medium-high heat. Add the fish and cook until opaque throughout, 1 to 2 minutes per side.
- Spread the tartar sauce on the buns; sandwich with the fish and lettuce. Serve with the salad and lemon wedges.