Make the compound butter: In a small bowl, combine the softened butter, minced garlic, chili powder, smoked paprika, kosher salt, and cayenne (if using). Mix well until fully combined and smooth. Set aside at room temperature, or refrigerate if making ahead.
Preheat your grill: Heat a gas or charcoal grill to high heat (around 450–500°F). Clean the grates well and lightly oil them using tongs and a folded paper towel dipped in neutral oil.
Grill the corn: Place husked ears of corn directly on the hot grates. Grill for 10–12 minutes total, turning every 2–3 minutes, until kernels are charred in spots and deeply golden all around. Let each side sit undisturbed for the full 2–3 minutes before turning to develop proper char and caramelization.
Apply the compound butter: During the final 1–2 minutes of grilling, brush or spread a generous amount of the compound butter over each ear of corn. Let the butter melt and sizzle directly on the hot corn on the grill.
Add toppings and serve: Remove corn from the grill and immediately transfer to a serving platter. Sprinkle each ear generously with finely grated Parmesan, a dusting of extra chili powder, and fresh cilantro if using. Squeeze fresh lime juice over the top. Serve immediately with remaining lime wedges on the side.
Notes
Meal Prep Tip: The compound butter can be made up to 7 days ahead and stored wrapped in the refrigerator, or frozen for up to 2 months. Simply slice off a pat when ready to use.No Grill? Use a cast-iron grill pan over high heat on the stovetop, or broil corn on a sheet pan 6 inches from the broiler, turning every 2–3 minutes.Storage: Leftover grilled corn keeps in the fridge for up to 3 days wrapped tightly in foil. Reheat in the microwave wrapped in a damp paper towel for 1–2 minutes, or on a hot grill pan.For full elote style: Spread a thin layer of mayonnaise or Mexican crema on the corn before adding butter and Parmesan for extra creaminess.