Unsalted butterpreferably high quality like Kerry Gold
Place butter in a sauce pan and melt on low heat.
Keep heating until it comes to a very low simmer and the top starts to look foamy.
When no more foam seems to be appearing (5 - 10 minutes), pour through a cheesecloth lined colander into a glass jar. Store in the refrigerator. (Yes, technically clarified butter is shelf stable, but since you clarified it yourself, it's better to be safe than sorry!)