Using food processor, use metal blade to process mushrooms with on/off burst until coarsley chopped, set aside.
Cut white and green part of onion into 1 inch pieces. Process with parsley, thmye and salt until finely chopped.
Melt 1/2 cup butter in wide frying pan. Add livers, mushrooms and onion mixture. Cook, stirring often over medium heat about 5-8 minutes, until livers are firm, slightly pink in center.
Add brandy and wine, heat to simmer, remove pan from heat. Cut remaining 1 cup butter into chunks.
Transfer liver mixture and liquid to processor bowl. Process to make a smooth puree.
With motor running, drop pieces of butter down feed tube and process until smooth.
Pour pate into 4-5 small containers. Cover and chill overnight or up to one week.
Freeze for longer storage.