Cut steak into strips about 2 inches long (with grain) and 1/8-inch thick (against grain). In a bowl or heavy plastic bag, mix sherry, tamari, and maple syrup. Add beef and toss to coat. Cover and refrigerate 30 minutes.
Combine all dressing ingredients in a tightly covered container; shake until well blended and set aside.
Heat a 10-inch nonstick skillet over medium-high heat until drops of water skitter when sprinkled on its surface. Add half of the beef; stir-fry until no longer pink, about 3 minutes. Remove beef and drain skillet. Repeat with remaining beef.
Combine greens, tomatoes, carrots, and green onions in a large salad bowl. Pour dressing over salad and toss until well coated. Divide salad mixture among serving plates and top with beef strips. Sprinkle with sesame seeds.