This is a wonderfully chewy, grassy salad that compliments main courses with a supple texture, for example, roasted salmon or tofu. For the best flavor, make this ahead of time and let it marinate for a few hours in the refrigerator.
In a large skillet, heat the olive oil over medium heat and add the shallots and 1 tablespoon salt. Cook until the shallots are translucent, 5 to 8 minutes. Stir in the wheat berries, cover with 5 cups water, and bring the water to a simmer. Cook, stirring from time to time, until the wheat berries are tender, 50 to 55 minutes. Taste the wheat berries for doneness: they should be tender but still slightly chewy. You may very well need to add water in small increments until the wheat berries finish cooking.
Make the vinaigrette and finish the salad:
In a large bowl, whisk the Dijon and grainy mustards with the sherry vinegar. Whisk in the canola oil and a splash of cold water. Stir the warm wheat berries into the mustard vinaigrette, and stir in the parsley and 2 teaspoons salt. Taste for seasoning, and serve.