Preparation Whisk together orange juice, syrup, oil, vinegar, onion, lemon juice, chipotle with adobo sauce, and salt in a bowl until combined well. Remove peel and any white pith from oranges with a sharp knife. Cut oranges crosswise into 1/4-inch-thick slices. Separate endive leaves and arrange with oranges on a platter, then drizzle with vinaigrette.