Heat a cast iron skillet over high heat until very hot. Add the oil, swirl, then add peppers in a single layer. Cook 2 minutes without moving until blistered on the bottom.

Flip peppers and cook another 1-2 minutes until charred all over and tender. Shake the pan for 30 seconds.

Pile peppers onto a plate, shower with flaky salt, and serve immediately with lemon wedges.