Slow-cooked onions add moisture and flavor to these lean beef burgers. A quick blend of mayonnaise, ketchup, relish and vinegar makes a perfect tangy, sweet and creamy "special sauce" for this burger. We love the dill relish here, but use sweet relish if you prefer it. Serve with sweet potato fries.

Classic Hamburger

Serves 4

Active Time: 45 minutes

Total Time: 45 minutes

1 medium onion, chopped

1 tablespoon canola oil

2 tablespoons ketchup, divided

2 tablespoons low-fat mayonnaise

2 teaspoons dill pickle relish

1 teaspoon distilled white vinegar

1 pound lean (90 percent or leaner) ground beef

2 tablespoons Worcestershire sauce or steak sauce

1/2 teaspoon freshly ground pepper

4 sesame-seed or other hamburger buns, toasted

4 slices tomato

4 leaves green-leaf lettuce

Preheat grill to medium-high (or see stovetop variation).

Combine onion, oil and 1 tablespoon ketchup in a medium saucepan. Cover and cook over medium-high heat, stirring often, until the onion is softened, 5 to 7 minutes. Reduce heat to medium-low, uncover and cook, stirring occasionally, until very soft, 5 to 8 minutes more. Transfer to a medium bowl and let cool for a few minutes.

Meanwhile, combine the remaining 1 tablespoon ketchup, mayonnaise, relish and vinegar in a small bowl. Set aside.

Add beef, Worcestershire (or steak sauce) and pepper to the onion and gently combine without overmixing. Form into four patties, about 3/4 inch thick.

Oil the grill rack (see note). Grill the burgers, turning once, until an instant-read thermometer inserted in the center registers 165 F, 4 to 5 minutes per side.

Assemble the burgers on toasted buns with the ketchup-mayonnaise sauce, tomato slices and lettuce.

Recipe notes: To oil a grill rack, oil a folded paper towel, hold it with tongs and rub it over the rack. (Do not use cooking spray on a hot grill.)

Stovetop variation: Coat a nonstick pan, preferably cast-iron (or a grill pan), with cooking spray and heat over medium-high heat for 1 to 2 minutes. Add burgers, reduce heat to medium and cook, turning once, until an instant-read thermometer registers 155 F (for pork and bison) or 165 F (for beef or chicken), 4 to 5 minutes per side.

Recipe Nutrition: Per serving: 375 calories; 16 g fat (4 g sat, 7 g mono); 71 mg cholesterol; 31 g carbohydrate; 4 g added sugars; 8 g total sugars; 27 g protein; 2 g fiber; 536 mg sodium; 518 mg potassium.

Nutrition Bonus: Vitamin A (41 percent daily value), Zinc (39 percent dv), Iron (26 percent dv), Folate (24 percent dv), Vitamin C (15 percent dv).

2 Carbohydrate Serving(s)

Exchanges: 1 1/2 starch, 1 vegetable, 3 lean meat, 1 fat

(EatingWell is a magazine and website devoted to healthy eating as a way of life. Online at www.eatingwell.com.)