- In a small bowl, whisk together all of the ingredients. Season with pepper. Refrigerate until ready to serve.
- With the rack in the middle position, preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper.
- Place the cabbage on the baking sheet and toss with the oil. Season with salt and pepper. Bake for 25 minutes or until the cabbage is tender. Let cool.
- In another bowl, combine the cooked barley with a third of the vinaigrette. Transfer to a serving platter and cover with the remaining ingredients. Drizzle with the remaining vinaigrette.
The barley can be cooked in advance and even frozen once cooked. For 3 cups (750 ml) of cooked barley, you will need to cook 3/4 cup (150 g) of barley in salted, boiling water for about 40 minutes.