Serves 4   Chicken   1-whole fryer chicken, quartered 2-tablespoons olive oil 1 ½ – teaspoon kosher salt ½ -teaspoon fine, freshly ground black pepper   Sauce   ¼ cup olive oil or clarified butter 2 large red bell peppers, seeded, cut lengthwise into strips about ½ inch wide 1 large yellow onion, sliced into…