1. Heat a skillet over medium-high heat. Add the corn and cook, turning occasionally, until charred in spots, about 8-10 minutes. Remove from heat and let cool.
2. Cut the kernels off the cob and place them in a large mixing bowl.
3. Add the cherry tomatoes, avocado, red onion, cilantro, jalapeño, and cotija cheese to the bowl.
4. In a small bowl, whisk together the lime juice, olive oil, chili powder, salt, and pepper.
5. Pour the dressing over the salad and toss to combine. Serve immediately or refrigerate for later.