Wrap the corn in plastic wrap, place it in a microwave-safe container, and heat in a 600W microwave for 3 minutes. Let it cool slightly, then cut it into thirds lengthwise and halve each piece.

In a bowl, mix the miso, ground sesame seeds, and mirin until well combined.

Heat a frying pan over medium heat and add the butter. Once melted, place the corn kernels side down and cook until golden brown.