Clarified butter

Clarified butter is the butter with the water and milk solids removed. It's great for cooking because it burns at a much higher temperature (400°F) than normal butter (250°F). It also keeps for a long period of time without going rancid.

Heat butter in a heavy sauce pan over low heat ("4" on my stove). This will take some time, about 20 minutes, but you can just let the butter melt then separate. You don't need to stir it or otherwise mess with it.

Resist the temptation to turn up the heat because the milk solids burn easily. Once foam starts to form on top of the butter, scoop it off and discard. Lower the heat to prevent boiling.   Once foam mostly stops forming remove from the heat and pour into a heatproof container suitable for pouring. I like to use a pyrex measuring cup.

Scoop off any foam that forms and let sit for several minutes. Gently pour into another container leaving the milk solids in the measuring cup and allowing only the pure butterfat into the storage container. I like to use an airtight glass storage container with a plastic top.

Let cool then refrigerate. It should keep for months. Clarified butter technically could be stored at room temperature, but since there's a chance you won't get all of the milk solids out, it's safer to store it in the refrigerator. Like butter, it can also be frozen.   Ghee is a form of clarified butter where the milks solids are browned before separating.