Black Bean, Tomato and Corn Salad

I started making this in college. It came about one night when I didn't have any ranchero beans to go with the fajitas I was making, so I improvised.

2 cups fresh or frozen and thawed corn kernels
1/2 cup finely chopped red onion
2 tablespoons seasoned rice vinegar
1 tablespoon extra-virgin olive oil
1 tablespoon lime juice
1/4 teaspoon sea salt
1/2 teaspoon ground black pepper 

1/2 teaspoon cumin

1 tablespoon chili powder
4 cups no-salt-added cooked black beans, rinsed and drained
1 Tomato, seeded and chopped
1 red bell pepper, cored, seeded and chopped
1/3 cup cilantro leaves, finely chopped

In a large bowl, whisk together vinegar, olive oil, lime juice, salt, pepper, cumin and chili powder to make a dressing. Add beans, corn, onion, bell pepper and tomato - toss until just incorporated. Cover and chill for about 2 hours. Add cilantro and toss again before serving.