1 1/2 lbs. ground beef chuck

4 sesame seed sandwich rolls, split, toasted

1 cup watercress or mixed spring greens

1 tablespoon curry powder

1 tablespoon Caribbean jerk seasoning

1 teaspoon salt

1/2 cup mayonnaise

1/4 cup plain yogurt

1 tablespoon fresh lime juice

2 teaspoons grated lime peel

1/4 teaspoon salt

Combine ground beef and seasoning ingredients in large bowl, mixing lightly but thoroughly. Shape into four 3/4-inch thick patties. Place patties on grid over medium, ash-covered coals. Grill, uncovered, 13 to 15 minutes to medium (160 degrees) doneness, until not pink in center and juices show no pink color, turning occasionally. Meanwhile, combine sauce ingredients in small bowl; set aside. Spread sauce on cut sides of rolls. Place a burger on bottom half of each roll; top evenly with watercress. Close sandwiches.