In a large bowl combine the marinade ingredients. Place the meat cubes in the bowl and turn in the marinade to coat evenly. Allow to stand at room temperature for 30 minutes, or cover and refrigerate for up to 4 hours.
Prepare the grill for direct cooking over high heat (450° to 550°F).
Thread the meat onto skewers, alternating with the tomatoes.
In a bowl whisk the dressing ingredients.
Brush the cooking grates clean. Grill the kabobs over direct high heat, with the lid closed, until the meat is cooked to your desired doneness, 6 to 8 minutes for medium rare, turning occasionally. Spread the lettuce leaves on a platter, top with the kabobs, and serve with the dressing.