Fill the stockpot about half full with fresh, clean water. The amount of water depends on how large the half-slotted insert is. If the insert dangles into the water when the pot is half-full, empty some of the water out, making it only about half full.
Drop the half-slotted insert into the stockpot. A half slotted steam insert features no holes on the bottom of the basket so steam foods can be buttered.
Drop 1/2 lb of butter into the half slotted insert.
Cover the pot and bring the water to a rolling boil.
Drop the live Florida lobster into the half slotted insert. Drop the remaining butter on top of the lobster. Cover the pan and let it steam for 30 minutes. Ordinarily a 1 lb. lobster steams completely cooked in 25 minutes, but the extra five minutes assures you that it is fully cooked.