Cut beef steak lengthwise in half, then crosswise into 1/8 to 1/4-inch thick strips. Combine 1/4 cup dressing and garlic in medium bowl. Add beef; toss to coat. Cover and marinate in refrigerator 30 minutes to 2 hours.
Heat large nonstick skillet over medium-high heat until hot. Add green beans and remaining 1/4 cup dressing; stir-fry 5 to 7 minutes or until crisp-tender. Remove from skillet; season with salt, as desired. Set aside.
Remove beef from marinade; discard marinade. Add 1/2 of beef to same skillet; stir-fry 1 to 2 minutes or until outside surface of beef is no longer pink. (Do not overcook.) Remove from skillet. Repeat with remaining beef.
Return green beans and beef to skillet; cook and stir 1 to 2 minutes or until heated through. Garnish with sesame seeds. Serve with rice, if desired.
