Preheat grill to medium high heat. Place corn directly on the grill grates. Grill, rotating every 8-10 minutes, until corn begins to char (about 30 minutes or shorter, depending on how hot your grill is). When corn is cool enough to handle, carefully cut the kernels from the cobs.
Meanwhile, in a small bowl, stir together Greek yogurt, garlic, chili powder, lime zest and 1/2 of the lime juice. Add water, 1 Tablespoon at a time, until salad dressing consistency is achieved.
In a large bowl combine kale, salt and remaining lime juice. Gently massage the kale for 15 seconds to soften.
To assemble the salad, toss together massaged kale, corn, dressing, queso fresco, and cilantro. Serve immediately with sliced avocado and pickled red onion.