Turns out the best summer app for entertaining is also the easiest. The more char, the better!
Heat oil in a medium cast-iron skillet over medium high. Once oil is hot, add shishitos and toss in skillet. Let sit untouched until bottom side achieves a char, about 4-5 minutes. Using tongs, flip the shishitos so all sides are charred. While still in pan, toss in lime juice. Remove from pan and season with flaky salt and cracked black pepper, to taste.
In a small bowl, whisk mayonnaise, sriracha, and oil. Serve with pepper immediately.