Melt butter in over med. heat in med. saucepan w/ pouring lip, stirring occasionally. After several minutes, a foamy layer will form on top of the butter, and the butter will start to simmer.
Once the butter simmers, reduce heat to med.-low. Continue cooking for approx. 10-15 min., gently scraping any milk solids that stick to the side or bottom of the pot, as the foam dissipates.
Continue cooking, scraping as necessary, for another 4-5 min. until a second foamy layer forms. Remove from heat. Rest 2-3 min.
Meanwhile, line strainer w/ 3-4 layers of cheesecloth. Pour butter through strainer into heat-safe measuring cup or mixing bowl w/ pouring lip. Discard brown solids or reserve for another use.
Let cool and transfer ghee to clean, dry jar and seal. Ghee should last at least 2-3 months stored in pantry or cupboard, or up to a year in refrigerator.