For each quart of oil:
- 1/2 cup water
- 1 teaspoon powdered gelatin
- After deep-frying, allow your cooking fat to cool to room temperature or slightly warmer.
- Measure into a small pot half a cup of water for every quart of used oil. Sprinkle it with one teaspoon of powdered gelatin per half cup of water, and let the gelatin hydrate for a few minutes.
- Bring the water to a simmer (you can do this on the stovetop or in the microwave), stirring, until the gelatin dissolves.
- Stirring vigorously and constantly, pour the gelatin/water mixture into the dirty oil. It should look very cloudy and relatively homogeneous at this stage.
- Cover the pot and place it in the refrigerator (or transfer the mixture to a separate container before refrigerating), then allow it to rest overnight.
- The next day, pour the oil from the top of the pot or container into a separate clean, dry pot.
- Discard the disk of gelatin that remains.
- The clarified oil is ready to use.
The first time you use the clarified oil, you’ll find that as it heats up, it will start to bubble a little bit. This is okay. Swirl the pan gently as it bubbles to help release any remaining droplets of water. It will eventually settle down until it’s ready for frying.