Preheat the broiler. Wash and dry the poblano pepper and place it on a rack about 6 inches below the heat. Broil until the skin chars and blisters, turning several times.
Watch carefully as times will vary. Remove from the oven and place the pepper in a clean paper bag, fold the top closed, and set aside to cool for about 10 minutes.
Reduce the oven temperature to 400°F and arrange the tomatillos in a single layer on a baking sheet. Season with a little salt and pepper and roast until slightly softened, about 5 minutes. Remove from the oven and allow to cool.
Once the poblano has cooled, peel off as much skin as possible and discard the seeds and stem.
Place the poblano and tomatillos in the work bowl of a food processor. Add the jalapeño, garlic, scallions, cilantro, and lime juice.
Pulse until the salsa reaches a consistency you like - we like ours a little bit chunky.
Taste and season with salt and pepper, transfer to a bowl, and serve with your favorite tortilla chips.