Step 1

Heat oil in 12-inch nonstick skillet over medium heat until shimmering. Add fish sticks and cook until deep golden brown and crisp, 3 to 4 minutes per side. Transfer to paper towel–lined plate.

Step 2

Combine mayonnaise, chili sauce, sriracha, and salt in large bowl. Transfer 2 tablespoons mayonnaise mixture to medium bowl and set aside. Add fish sticks to remaining mayonnaise mixture and toss gently to coat. Divide fish evenly among tortillas.

Step 3

Whisk lime juice into reserved 2 tablespoons mayonnaise mixture. Add lettuce and toss to coat. Divide lettuce mixture, radishes, and scallions evenly among tacos. Serve.