Step 1. Lock victim in cage. Movement must be impossible. Step 2. Force feed victim, avoiding stomach rupture if possible. Step 3. When victim's liver has grown to several times it's healthy size, viciously slaughter victim. Step 4. Harvest victim's liver and profit?!?!
This is not a sequel to "Silence of the Lambs", it's the production of the French delicacy Foie Gras. Check out this video that takes a satirical look at Foie Gras production in France.