If you are concerned about presentation for your guests, you can remove the head of the trout by placing your knife directly under the gills and slicing through.
Prep your charcoal grill for a single layer fire and clean and grease the grate well. In a large skillet, cook the bacon until crispy, over medium heat.
Remove from pan and place on paper towel-lined plate to drain. Add the onions and pepper to the skillet and season with salt. Cook for about 5 to 7 minutes.
Toss in the bacon, apple cider vinegar, and season with pepper if desired. Rub the inside of the fish with oil and season inside and out with salt and pepper.