1. Roast potatoes: toss cubes with oil, salt; bake 425 °F 25 min, turning once.
2. Whisk dressing: maple, vinegar, Dijon, pinch pepper.
3. Massage kale with 1 tsp dressing to soften.
4. Combine warm potatoes, kale, cranberries, pecans, feta; toss with remaining dressing. Serve warm or room temp.