To cooke the wheat berries: Rinse the wheat berries. Bring the vegetable stock with salt to a boil and add the wheat berries. Reduce the heat to medium-low and simmer for 30-40 minutes until soft but still chewy. Drain and allow to cool. To toast the walnuts, preheat oven to 350°F. Arrange walnuts on a cookie sheet in a single layer and bake 8 to 10 minutes, checking frequently to prevent burning. Let cool completely.To make the vinaigrette: Combine all ingredients in a small bowl and whisk until emulsified.All three of these steps preparations can be done well in advance.
Heat the olive oil in a small skillet over medium-high heat and saute the onions and until golden brown, 7-8 minutes. Add the cumin and cook for another minute. Add the carrots and salt and cook for 3-4 minutes until softened. Add the thyme, oregano, and chopped chipotles and cook for another 2 minutes. Let cool.
In a large mixing bowl, combine the onion/carrot mixture with the wheat berries and all remaining ingredients. Pour over the vinaigrette and stir to thoroughly combine. Let the salad sit for at least 30 minutes before serving. Best served at room temperature. Store leftovers in the refrigerator.
Notes
You can also substitute the wheat berries for quinoa, barley, brown rice, or practically any whole grain of your choice. Though it's not a grain, another alternative is couscous.