Step 1

Microwave tomatoes, sugar, vinegar, ⅛ teaspoon salt, and ⅛ teaspoon pepper in bowl until mixture is thickened, about 8 minutes, stirring halfway through microwaving. Let chutney cool completely, then stir in scallion greens and 1 tablespoon cilantro. Season with salt and pepper to taste; set aside for serving. (Chutney can be refrigerated for up to 3 days.)

Step 2

Pulse salmon in food processor until there is even mix of finely minced and coarsely chopped pieces, about 2 pulses, scraping down sides of bowl as needed. Stir panko, yogurt, lemon juice, scallion whites, remaining ⅛ teaspoon salt, remaining ⅛ teaspoon pepper, and remaining 3 tablespoons cilantro together in large bowl. Fold in salmon gently until just combined.

Step 3

Lightly spray base of air-fryer basket with canola oil spray. Using your lightly moistened hands, divide salmon mixture in half, shape into 2 lightly packed balls, and flatten each ball gently into 1-inch-thick patty. Press center of each patty with your fingertips to create ¼-inch-deep depression.

Step 4

Arrange patties in prepared basket, spaced evenly apart. Place basket into air fryer and set temperature to 350 degrees. Cook until burgers are lightly browned and centers are still translucent when checked with tip of paring knife and register 125 degrees (for medium-rare), 6 to 8 minutes, flipping burgers halfway through cooking. If desired, arrange bun tops and bottoms cut side up in now-empty basket. Return basket to air fryer, set temperature to 400, and cook until buns are lightly toasted, 4 to 6 minutes. Serve burgers on buns, topped with chutney and lettuce.