Soak onion in olive oil until onion is sweet. Cut corn off husks into a bowl and chop grape tomatoes, and bunch of cilantro. Drizzle some oil from onions on top and set aside. Add ground pepper, white pepper, and salt to taste on corn. Mix corn and tomato mixture. Mix well. Juice both lemons pit the juice. Set aside. Chop green onions, and mix with washed and drains black beans (if adding). Toss and add to main salad. Add Olive oil, onions, and lemon juice. Toss well and wait 10 min to serve.