Combine all dressing ingredients and stir until sugar is dissolved. Set aside.
Clean the lettuce and tear into bite sized pieces.
Cut the cucumber lengthwise and slice into thin half moons.
Cut the roma tomatoes into thin wedges.
Slice the onion into thin slices.
Season the steak with salt and pepper. Grill to your desired temperature.
Remove the meat from the grill and let it rest for 5 minutes before slicing.
Slice the steak and arrange it on a platter. Pour half the dressing over the steak.
Serve the steak with the salad ingredients and top with more dressing if desired. You can also assemble all the ingredients together on a platter before serving.