In a food processor, process the kale, garlic, lemon zest, 1/2 t salt, pinch pepper, walnuts, and cheese briefly. Through the shoot on top with the motor running, slowly add the 1/3 c olive oil. If you want a looser pesto, add more oil at this point to your desired consistency.
Using a mandolin with the medium julienne cutter in - or just use the large holes on a cheese grater - lay a zucchini flat on it and push to make the long "spaghetti" of zucchini. Repeat until you feel that you are hitting the seeds (you'll feel it), then rotate a 1/4 turn and repeat. Keep repeating with all the zucchini.
In a large nonstick skillet, heat the 1 tablespoon olive oil on medium-high heat. Add the zucchini strings with a pinch of salt and heat, tossing occasionally, until the zucchini just starts to soften. The zucchini will keep cooking a bit once taken off the heat, so take them off the heat immediately once they soften. We don't want mush :) Take the half lemon, and squeeze over a little juice on the zucchini at this point.
Cook the spaghetti to al dente according to package directions in heavily salted water. Add to the cooked zucchini. Add the kale pesto and work it all together. Serve topped with additional parmigiano cheese. Yield: 4 servings.