A quick tip: Because kale leaves are considerably tougher than basil, it helps to blanch it first before blending with the other pesto ingredients. Just give the kale leaves a dip in boiling water (15 seconds or so, just enough to wilt them and bring out their greenest color). Then plunge them into an ice water bath to stop the cooking and set the color. This will tenderize them for puree, and also make the pesto a brilliant emerald green.
Use kale pesto any way you'd use basil pesto: stir it into pasta dishes, top bruschetta and pizzas, and so on. One of my favorite ways to use it is in grain salads, served cold or at room temperature. Cook a cup or so of your favorite whole grains (like farro, wheatberries, or millet), then dress them with olive oil, vinegar or lemon juice, and salt and pepper while still hot so they absorb the flavorings. Let the mixture cool (so it doesn't discolor the pesto), then stir in pesto to taste. Add chopped tomato, cuke, and onion, and finish with a little chopped parsley. Great for picnics or light but satisfying lunches.