Peel plantains, cut in half widthwise and then cut in half lengthwise.
In a large pot or deep-fryer preheat vegetable oil to 325 degrees F. Add the plantains to the oil and fry for 5 minutes. Remove them and place on a flat surface. Increase heat to 375 degrees F. With a metal flat spatula press down onto the plantains until they are flat, less than 1/4-inch. Using a knife to help scrape the plantain off the spatula, deep-fry the plantains again for 3 minutes. Pull them out and season both sides with salt and pepper.
Combine the bread crumbs, cayenne pepper, black pepper, salt, paprika, oregano, thyme, garlic powder, onion powder to create Cajun spice.
Dip each piece of steak into 4 ounces melted butter and then into the Cajun spice, covering both sides of the steak.
Spread the remaining melted butter onto a flat top grill or metal skillet, place the steak on top and cook on both sides until medium or preferred degree of doneness. After the steak is done slice it thin against the grain.
Combine the mayonnaise and chipolte sauce to create chipolte mayonnaise.
Onions: In a mixing bowl combine flour, salt, pepper, garlic powder, onion powder, and a pinch of cayenne pepper. Slice the onion very thinly. Place in the flour mixture. Squeeze the slices of onions as you are mixing them with the flour mixture. Shake off the excess flour.
Drop a little bit of onions into 375 degree F oil at a time to prevent them from sticking together. Cook for 1 minute and 30 seconds or until golden brown. Drain on paper towels.
Build a sandwich by layering 1 fried plantain, about 1 tablespoon chipolte mayonnaise (spread coast to coast on bottom plantain), sliced steak, and 1/3 cup of the shredded cheese. Place under the broiler for a minute or 2 or use the microwave to melt cheese. Then continue layering 1/2 cup of fried onion, 1 more tablespoon chipolte mayonnaise, spread coast to coast on top plantain, fried plantain. Cut sandwich in half before serving.