Heat a grill to medium-high, approximately 400–450°F (200–230°C). Make sure the grates are clean so the corn develops attractive char marks without picking up unwanted residue.

In a small bowl, stir together the mayonnaise, Mexican crema or sour cream, chili powder, optional cayenne pepper, and salt. Mix until smooth and evenly seasoned, then set the sauce aside while the corn cooks.

Lightly brush the husked corn with the vegetable oil or melted butter. Use just enough to help prevent sticking and encourage light browning without making the kernels greasy.

Grill the corn for 8–12 minutes, turning frequently so it cooks evenly on all sides. Remove it when the kernels are tender and scattered with lightly charred spots, taking care not to leave it stationary long enough to dry out.

While the grilled corn is still hot, spread each ear generously with the mayonnaise mixture. The heat helps the sauce cling to the kernels and creates a creamy coating from end to end.

Roll each sauced ear in the finely crumbled Cotija cheese, or sprinkle the cheese over the corn if that is easier. Add more Cotija for a saltier, cheesier finish.

Finish the elote with chopped cilantro, an additional dusting of chili powder, and a squeeze of lime juice. Serve immediately with lime wedges so everyone can add more citrus at the table.