Preheat the grill to medium-high heat (about 400°F to 450°F).
Husk the corn, removing the silk and any damaged kernels.
In a bowl, mix the softened butter, lime juice, chili powder, garlic powder, salt, and black pepper until well blended.
Brush the corn with the chili lime butter mixture generously, reserving some for later.
Place the corn on the grill and cook for 10-15 minutes, turning occasionally, until charred and tender.
Remove the corn from the grill and brush with any remaining chili lime butter.
Sprinkle with chopped cilantro if using, and serve hot.