Melt butter over medium heat. Add onion and cook for about 10 minutes or until golden. Add liver and garlic, cook until livers are browned but still pink inside. Stir in brandy or cognac and cook 5 additional minutes. Place all ingredients into food processor and process until smooth.
Spoon mixture into serving bowl, cover and refrigerate overnight or at least 4 hours.Let stand at room temperature for 30 minutes prior to serving.
I serve this with assorted crackers, Triskets and Club crackers are great.