Dehydrator or temperature controlled fermentation chamber
1000grams2.2lbs lean meat (I used lamb tongues but that isn't economical for most people)
200gramsKoji rice1 package, see supplier in notes
Sterilize and sanitize fermentation vessel, or put it through the dishwasher if possible. Cut the meat into pieces that will fit in a meat grinder.
Mix the cut meat with the koji rice, then put through the meat grinder. Mix the salt into the ground meat-rice mix, then carefully mix in the water. You can also buzz the whole mixture with a hand blender before putting in the fermentation vessel.
Carefully ladle the meat slurry into the fermentation vessel, press down firmly with plastic, put on the lid, then put it in the dehydrator and set the temperature to 140 degrees. Check frequently on the garum during the first week and skim any fat that rises to the surface, and refresh plastic if needed. Skim the fat weekly after the first week. After a couple weeks, I didn't have to skim mine.
After a couple days, you'll see a raft forming, and gentle bubbles in the mix letting you know the magic is happening. Remove the garum after 30 days, carefully strain out the liquid, then chill the liquid until any fat has congealed on top and can be easily spooned off.
Strain the mixture again for good measure. Finally, tare a scale with a mason jar on it weighing in grams, pour in the garum, adjust the weight back to 800 grams with fresh water (or leave it as-is if you prefer it stronger), screw on the lid, label, date, and refrigerate until needed.