Stir pomegranate juice with lemon juice and Dijon. Whisk in 2 tbsp (30ml) olive oil. Season with ¼ tsp salt and pepper.
Preheat oven to 350ºF. Peel beets. Cut small beets in half, and large beets into quarters. Toss with 1 tablespoon (15 mL) olive oil, cumin, remaining salt and pepper in a large bowl. Transfer to a parchment-lined baking sheet and cover loosely with foil. Bake for 40 minutes, or until tender. Remove from oven.
Combine kale with feta and walnuts in a large bowl. Add vinaigrette and toss to coat. Divide salad between plates. Slice beets into ¾-inch wedges and place over salad.