Preheat oven to 200°C/400°F. Add the kale to a large salad bowl. Drizzle with 1 tbsp of olive oil and season generously with salt. Use your hands to vigorously massage the kale. Allow to sit for at least 30 minutes and preferably 1 hour at room temperature.
Add the beans to a mixing bowl. Drizzle with 2 tsp of olive oil, sprinkle over the za'atar and season generously with salt and pepper. Stir to combine and spread over a parchment-lined baking sheet. Roast until golden and lightly crisp 15-20 minutes.
Add the walnuts to a rimmed baking sheet. Move to the oven and toast until fragrant, 5-7 minutes. Set aside.
To the bowl with the kale, add the onion, olives, feta, orange segments and parsley. Add in the roasted beans and walnuts. Drizzle with the dressing and toss to combine. Serve.