Bring to boil a large pot of lightly salted water. Add the spelt berries and cook them partially covered for 50-60 minutes or until they are tender. Drain and spread them out on a rimmed baking sheet to cool.
To make the dressing, combine the lemon juice, salt and maple syrup in a small bowl. Slowly pour in the olive oil, whisking as you do.
In a large bowl, combine the spelt, cranberries, walnuts, onion, thyme, ¼ teaspoon of salt and ¼ teaspoon pepper. Drizzle with half of the dressing and toss to combine. Add the kale and more of dressing to taste. Toss until well combined and the kale is evenly coated with dressing. Top with feta to serve.