Wait for the butter to change color from creamy yellow to a clear yellow where you can see visible milk solids floating.
Strain the milk solids through a fine mesh strainer lined with several layers of cheesecloth into a glass or STURDY plastic bowl. (This is important. Do not use cheap glass as it can crack with the drastic temperature change and cheap plastic can melt.)
If you want to make "brown butter," strain only half the butter. If you do not, strain all the butter (twice if you have a dairy allergy and want to be sure all milk solids are removed.)
To make "brown butter", continue cooking until the milk solids begin to burn and the butter turns a reddish-brown. The ghee will start to smell like caramel and heaven. If it starts sticking to the bottom of the pot, it is probably ready to strain.
Again, strain through a fine mesh strainer lined with several layers of cheesecloth into a bowl.
Once the ghee has cooled a little, pour into glass jars and store at room temperature. As it cools, it will become opaque and might look buttery. This is normal. (When heated, it will become transparent again.)
**This recipe creates three jars of ghee. You can make as much as you want when you make it, just make sure you have a large enough pot and enough jars for storage. If you only have one pound of butter, use a medium sized pot.