Peel back husks, leaving them attached at the base of the ear. Remove and discard silk; pull husks back over corn. Place a triple thickness of all-white paper towels in the microwave. Place ears, side by side, on towels. Microwave on high 8 to 9 minutes or until crisp-tender.
Meanwhile, in a small bowl, stir together butter, cilantro, lime zest and juice, chili powder, 1/8 teaspoon salt, and a pinch of pepper until blended.
Remove husks; serve with cilantro-lime butter.
Cilantro, lime, and chili powder are a classic Mexican combination. For a different taste, try substituting fresh basil for the cilantro, and lemon zest and juice for the lime when making the butter. Add one small garlic clove, finely chopped, and omit the chili powder.