In a medium bowl, combine the onion, grapes, and rice vinegar; set aside while cooking the chicken.

In a large skillet, heat the oil over medium-high heat. Add the chicken and cook, stirring frequently until just cooked through, about 6-7 minutes. Season chicken with salt and pepper. Stir in the chiles, fish sauce, lime juice, cilantro, and mint.

Divide the rice between 4 serving dishes and top with the chicken, cabbage, and the marinated onion and grape mixture; sprinkle with peanuts.