Combine the oil, vinegar, SunButter or peanut butter, and sesame oil. Season to taste with a pinch of salt and pepper. Add the red onion and let sit while preparing the rest of the slaw ingredients or at least 5 minutes.

In a large mixing bowl, combine the coleslaw mix, red pepper, and cilantro. Pour on the dressing and mix well. Taste and add more salt and pepper, if desired. Transfer to a serving dish, sprinkle with sesame seeds, and serve. The slaw is best served within an hour of preparing.