Brush each husked ear of corn lightly with the vegetable oil to prevent sticking and to promote even charring. Sprinkle the corn with the kosher salt.

Place corn on the preheated grill. Grill with the lid closed for 10–12 minutes, turning every 2–3 minutes, until kernels have even char marks and are tender when pierced with a knife.

Remove corn from the grill and let rest on a tray for 2 minutes so it’s safe to handle but still warm for spreading the sauce.

Creamy Coating

While the corn grills, in a medium bowl combine mayonnaise, sour cream, fresh lime juice, minced garlic, chipotle chili powder (or smoked paprika), and black pepper. Whisk until smooth and taste; adjust lime, salt, or chili powder to preference.

If the mixture seems very thick, add 1 teaspoon of water or more lime juice at a time to reach a spreadable consistency.

Assembly and Toppings

Using a brush or a spoon, evenly coat each warm ear of grilled corn with the creamy sauce, rolling the corn to cover all sides.

Immediately sprinkle each coated ear with a generous amount of crumbled cotija (or queso fresco), pressing lightly so the cheese adheres to the sauce.

Scatter chopped cilantro over the corn and dust with extra chili powder or cayenne if you like more heat.

Serve each ear with a lime wedge. Encourage diners to squeeze lime over the corn just before eating.