Plantains are like bananas with much thicker armor. You need to actually slice through the skin before you can pull it off; make a long vertical cut in the plantain skin and then pull the skin off with your fingers. Slice it as you would a banana.
Heat some canola oil in a frying pan on medium high. Add the sliced plantains and cook continously until they are soft and golden brown. While they're cooking, you can also sort of smoosh them down with the back of the spoon (or utensil) you're using so they're kind of mushy and not quite hard. I think this releases more of the sweetness, but really it just made them a little bit softer in the salad, so that's good too.
Dice the tomatoes, drain the black beans and chop the cilantro.
Combine hot plantains with the rest of the vegetables, toss, and then add in the chopped avocado and the white cheese.
5. Assemble dressing (olive oil, vinegar and sugar), throw it on, then toss to coat.