Bring a large pot of salted water to a boil and cook the pasta until just al dente according to package directions. Drain, rinse briefly under cold water to stop cooking, and set aside to cool slightly.

While the pasta cooks, heat a large skillet over medium-high heat. Add olive oil or butter. When it shimmers or the butter foams, add the corn kernels in a single layer.

Let them sear undisturbed for 2–3 minutes so golden-brown kernels form, then stir and cook another 2–3 minutes until a few kernels are nicely charred.

In a medium bowl, whisk together mayonnaise, sour cream or crema, lime zest, lime juice, minced garlic, chili powder, cumin, and a generous pinch of salt. Taste and adjust lime, salt, or spice for a balanced flavor.

In a large mixing bowl, combine the drained pasta, blistered corn, chopped cilantro, and red onion or scallions.

Pour the dressing over the warm mixture — warm pasta helps the flavors meld. Toss gently but thoroughly so every piece gets a creamy coating.

Fold in the crumbled cotija or feta and any optional add-ins like black beans or diced avocado (add avocado right before serving to avoid browning).

Chill for 20–30 minutes if you prefer it cold, or serve immediately at room temperature. Garnish with extra cilantro, a sprinkle of cheese, and an extra lime wedge.