Cut beef across the grain into thin slices.

Combine lemon peel, juice, 2 tablespoons sugar, sesame oil, 1 teaspoon salt and black pepper in medium bowl.

Add beef; toss to coat.

Cover and refrigerate at least 30 minutes.

Combine water, vinegar, remaining 4 tablespoons sugar and 1/4 teaspoon salt in small saucepan; bring to a boil.

Boil 5 minutes without stirring until syrupy.

Stir in crushed red pepper; set aside.

Remove beef from marinade; discard marinade.

Thread beef onto metal or wooden skewers (Soak wooden skewers in hot water 30 minutes to prevent burning).

Grill beef over medium-hot briquets about 3 minutes per side until cooked through.

Grill tortillas until hot.

Place lettuce, beef, mint and cilantro on tortillas; drizzle with vinegar mixture.

Roll tortillas to enclose filling.

Garnish with star fruit, bell pepper and orange peel strips.