Sauté onion in the butter until translucent, then add livers and cook until liver is firm and light colored all through.
Chop cooked liver and onion coarsely with the rest of the ingredients. Can be ground in meat grinder, but do not use a food processor or blender.
This is delicious spread on thinly sliced rye bread, or crackers. Kosher preparation would not use any butter, just schmaltz.
Barbara Wingfield, from Leahbell Gardner