1 medium red onion, sliced crosswise into ½-inch rings
1 large poblano chile, seeded and quartered
1 large red bell pepper, seeded and quartered
1¼ teaspoons kosher salt, divided, plus extra if needed
½ teaspoon freshly ground black pepper, divided, plus extra if needed
¼ cup red wine vinegar (plus more if needed)
3 tablespoons extra-virgin olive oil, divided
2 garlic cloves, very thinly sliced
1 cup fresh basil leaves
4 avocados, halved and pitted
¼ teaspoon chile powder
Directions
Build a medium fire in a charcoal grill, or heat a gas grill to medium-high. Use tongs to dip a folded paper towel into a small bowl of canola oil, then use it to grease the grill grates. To a separate small bowl, add the onion rings, poblano quarters and red pepper quarters, season with ½ teaspoon of the salt and ¼ teaspoon of the pepper, and toss to coat. Place the vegetables on the grill and cook until charred on both sides, about 12 minutes total. Transfer the onions to a medium bowl. Slice the red pepper quarters lengthwise into 1-inch-wide strips, add them to the onions and stir in the vinegar.
To a small heat-safe skillet set on the grill, add 2 tablespoons of the olive oil and the garlic and cook until soft but not browned, stirring occasionally, 3 to 5 minutes. Add the basil and stir until wilted, 15 to 30 seconds. Pour the mixture over the vegetables.
Rub the cut side of the avocados with the remaining 1 tablespoon of olive oil, season with the remaining ¾ teaspoon of salt and sprinkle with the chile powder. Grill the avocados cut side down until they are gently warmed and grill-marked, about 3 minutes. Serve with the pepper salad, salt and pepper to taste and bread, if using.