Bring a large pot of salted water to a boil. Cook pasta according to package directions until al dente. Drain and rinse under cold water to stop cooking and cool completely.

Heat a large nonstick or cast-iron skillet over high heat. Add the corn kernels in a single layer and cook without stirring for 1–2 minutes to get a char. Stir occasionally and continue cooking until kernels are blackened in spots, about 5–7 minutes total. Remove from heat and let cool.

In a small bowl, whisk together mayonnaise, sour cream, lime juice, chili powder, garlic powder, and salt until smooth and well combined.

In a large bowl, combine the cooled pasta and charred corn. Pour the dressing over the top and toss until everything is evenly coated. Gently fold in the crumbled cotija cheese and chopped cilantro.

Transfer the salad to a serving bowl. Sprinkle extra cotija, cilantro, and a light dusting of chili powder on top. Serve immediately with lime wedges on the side, or chill for 30 minutes to let the flavors meld.