Set the top oven rack as high as it will go. Preheat the broiler.
Rinse peppers and pat dry. For each pepper, use a knife to cut a circle around the stem to remove and discard it. Cut the pepper in half the long way (from top to bottom) and remove the membranes and seeds, discarding them.
Line up the pepper halves on a foil-lined sheet pan with sides, flattening the peppers a bit with your hands. Broil the peppers for 10-12 minutes, or until they are blackened all over.
Place the blackened peppers inside a clean, brown paper bag and fold the top closed. (A plastic Ziploc bag will create extra steam and cook the peppers more, but it's OK to use if you don't have a brown bag.) Keep the peppers in the bag for 20-30 minutes to enable the skin to be removed easily.
While the peppers are steaming in the bag, peel and slice your garlic.
After 20-30 minutes, peel the peppers with your fingers or a knife. (This gets messy, but it helps to wear food-prep gloves, if you have them.) Blot the peppers with paper towels to absorb any liquid and cut the peppers into strips about 2 inches wide.
Heat the olive oil in a 12-inch skillet over medium-high heat. Add the garlic slices and cook them for a couple minutes before adding the peppers to the pan. Gently toss the peppers to mix with the oil and garlic. Add salt and pepper. Lower the heat to medium and sauté the peppers, stirring occasionally, for about 8 minutes, or until the garlic is done to your liking.
Garnish with fresh parsley, if desired. Serve the peppers at room temperature with crusty bread. Store leftovers in the refrigerator for up to five days.
To serve leftover peppers after they've been refrigerated, let them sit out at room temperature for 30 minutes first. Or, just heat them briefly in the microwave or in a pan on the stove to take the chill off.
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Notes
If you'd rather char peppers on the stove instead of under the broiler, you can turn the heat on the highest setting and place whole peppers on the burners to char in the flames. Turn the peppers with tongs as needed. This is the traditional way to do it, but I find it safer to roast the peppers under the broiler.
If you have food-safe gloves, wear them when peeling the charred peppers. This will prevent your fingertips from blackening.
My family prefers to use regular olive oil here, since it's more mild than extra virgin. Use what you like.