Technically these would be microwave banana splits because we didn't have a fire going but, same thing.
Slice a wedge out of an unpeeled banana and fill with marshmallows and chocolate chips. If making them in the campfire you would wrap them in aluminum foil and throw them in the fire for a few minutes.
For the microwaved version, set the timer on high for about 1 minute 45 seconds to 2 minutes. Eat with a spoon Spark said, "These look gross but they sure are good!"