Place kale in a large bowl and add sea salt. Massage salt into the kale for 30-45 seconds, until the kale starts to wilt and let it sit for a few minutes. Meanwhile, whisk together lemon juice, olive oil, cumin and cayenne pepper.
Pour vinaigrette onto kale and massage, so each leaf is coated in vinaigrette.
Toss kale salad with olives and tomatoes, and season with salt and pepper. Let the flavors marinate together for at least 15 minutes before serving.