Add the butter to a medium pot with high sides and heat over medium-low heat until the butter has melted and is slightly foamy. Use a spoon to skim the foam off the top several times as it rises to the surface.
Reduce heat to low and continue cooking until the milk solids have browned but not burned and have sunk to the bottom. Place a mesh strainer lined with a piece of cheesecloth or a coffee filter over a jar. Then pour in the ghee, being careful to leave the browned bits in the pan.
Let the jar cool completely before placing in the fridge. Ghee may be stored up to 1 month in the fridge.