• 1 Tbsp rice wine vinegar
• 2 Tbsp grated peeled fresh ginger
• 2 cloves garlic, grated
• 2 Tbsp peanut oil
• 2 Tbsp Asian sesame oil
• 2 Tbsp soy sauce
• 2 Tbsp honey
• 1 Tbsp chopped cilantro
• 1/3 jalapeno, seeded and minced
• Ground white pepper
• 1 ½ lbs tuna (1 ¼ inch thickness), cut into 1 inch cubes
• 1 large red bell pepper cut into 1 inch squares
• 1 large sweet onion cut into  1 inch squares
• 6 metal skewers
• Additional chopped cilantro

Directions

1. Whisk first 9 ingredients in medium bowl to blend. 
2. Season to taste with ground white pepper. 
3. Transfer 3 Tbsp of marinade to a small bowl; reserve.
4. Add tuna to remaining marinade in medium bowl and toss to coat. 
5. Refrigerate at least 30 minutes and up to 45 minutes.
6. Spray grill rack with non-stick spray.   Prepare barbecue to medium high heat.
7. Alternate tuna cubes, bell pepper and onion on each of the metal skewers.  
8. Grill to desired doneness, turning frequently, about 4 minutes total for medium rare.
9. Transfer to platter and drizzle with remaining marinade.  Sprinkle with chopped cilantro.

Source: Tuna Kebabs with Ginger-Chile Marinade