Why This Recipe Works

We tossed the beans and tomatoes with salt and pepper first thing and allowed them to sit, which ensured they were seasoned thoroughly. While they macerated, the tomatoes released flavorful liquid, which we incorporated into the salad to flavor the whole dish. And a bright, basil-flecked vinaigrette made a piquant finishing drizzle for seared cod as well as a dressing for the white bean, tomato, and arugula salad.

Before You Begin

Haddock, hake, and pollock are good substitutes for the cod.

Instructions

Toss beans, tomatoes,  ½ teaspoon salt, and ¼ teaspoon pepper together in large bowl.  Process 7 tablespoons oil, basil, vinegar, shallot, mustard,  ½ teaspoon salt, and ¼ teaspoon pepper in blender until mostly smooth, about 30 seconds.

Pat cod dry with paper towels and sprinkle with remaining  ½ teaspoon salt and ½ teaspoon pepper. Heat remaining  1 tablespoon oil in 12-inch nonstick skillet over medium-high heat until  shimmering. Add cod and cook until both sides are lightly browned and cod registers 140 degrees, about 6 minutes per side.

Add ¼ cup dressing and  arugula to bean mixture and toss  to combine. Divide salad among  4 serving bowls and top each with  1 piece cod. Drizzle cod with remaining vinaigrette. Serve.