Pomegranates and orange slices add a splash of color to this flavorful winter salad. Try blood oranges, if they're available; they make a most dramatic statement with their ruby-red flesh.
Slice the oranges crosswise into rounds. If your oranges are very large, cut each round in half.
Place the orange juice in a small pan and reduce over medium-high heat until the juice has concentrated to about 3 tablespoons. Place the reduced orange juice in a small jar with a lid. Add the vinegar, honey and olive oil, and shake vigorously to blend. Season to taste with salt and pepper.
Place the greens in a bowl and toss with some of the dressing to coat the leaves. Divide among 4 salad plates, or arrange the greens on a shallow platter. Arrange the orange slices and avocado wedges on each salad, then sprinkle with the pomegranate seeds and hazelnuts. Drizzle on more dressing as desired. Serve immediately.