Prepare the mayonnaise mixture and cook the steak up to a day in advance. There's no need to reheat it; just slice the steak about an hour ahead, and leave at room temperature.
1/4 cup fresh orange juice
1/4 cup low-sodium soy sauce
2 tablespoons mirin (sweet rice wine)
2 tablespoons honey
2 teaspoons grated peeled fresh ginger
1/2 pound flank steak, trimmed
1/2 cup reduced-fat mayonnaise
2 teaspoons wasabi paste
2 teaspoons rice vinegar
24 baked rice crackers
Fresh chive pieces (optional)
How to Make It
To prepare steak, combine first 6 ingredients in a large zip-top plastic bag; seal. Marinate in refrigerator 24 hours, turning occasionally.
Remove steak from bag, and discard marinade. Heat a grill pan over medium-high heat. Coat pan with cooking spray. Add steak to pan; grill 6 minutes on each side or until desired degree of doneness. Remove steak from pan; let stand 10 minutes. Cut steak diagonally across grain into thin slices; cut slices into 2-inch pieces.
Combine mayonnaise, wasabi paste, and vinegar, stirring well. Spoon 3/4 teaspoon mayonnaise mixture onto each cracker. Divide steak evenly among crackers; top each with 1/4 teaspoon mayonnaise mixture. Garnish with chives, if desired.