Preheat the outdoor grill or broiler to medium high-high
If using the grill, put peppers directly on the grill grates and close lid. If using the broiler, put the peppers on a parchment paper lined tray and keep the oven door slightly open.
Once peppers start to brown or char, turn them using tongs. Keep turning until all sides are browned or charred.
Approx cooking time is 20 minutes.
Take peppers off the grill or out of the broiler and let them rest until cooled, approx. 1/2 hour.
While peppers are cooling, mix olive oil, minced garlic, kosher salt and pepper in a bowl.
Once peppers have cooled, peel them, remove the seeds and then slice.
Put peppers into the olive oil mixture.
Adjust seasoning to taste.