Shishito peppers usually get this treatment — you'll find blistered shishito peppers on menus at Japanese restaurants, and they've become a trend that chefs in other types of restaurants are using, too. There's no reason you can't use the same technique to enjoy your banana peppers.
To blister banana peppers, wash and dry them thoroughly. Heat a cast iron skillet over medium high heat, and add 1 tablespoon of peanut oil or avocado oil. Swirl the pan to coat it with the oil. Once the oil is hot, add the peppers. Let them split and char in spots, turning them occasionally with a pair of tongs. Remove them from the pan and salt them immediately. Serve them while they're hot.