Transfer the shishito peppers to a colander and rinse with cold water.

Pat the peppers dry using a paper towel or a kitchen towel.

Heat a large cast iron skillet (I recommend using a 12-inch cast iron) over medium-high heat with two teaspoons of avocado oil. Wait until the skillet is sizzling hot before adding the shishito peppers to the hot pan. You can test whether or not the skillet is ready by carefully flicking a tiny drop of water on the skillet. If it sizzles aggressively, it is ready. Cook the peppers in a single layer for 6 minutes, stirring them well at each 1-minute increment, until the peppers have a nice char.

Add the garlic and butter and stir well. Continue cooking for another 2 minutes, or until the peppers have reached your desired level of doneness.

Sprinkle the garlic butter shishito peppers with a little salt and black pepper and serve as an appetizer or side dish! You can also drizzle some fresh lemon juice or fresh lime juice over the peppers or serve with lemon wedges.