Sauté onion in 1/2 cup butter until golden, about 5 minutes. Add mushrooms and chicken livers; cook, stirring occasionally, until chicken livers are tender, about 5 minutes. Remove from heat. Add rest of butter, seasoned salt, lemon juice, pepper and cayenne. Stir until butter melts. Then divide mixture into 4 parts. In electric blender at high speed, puree the chicken liver mixture, one part at a time, adding 2 of the hard-cooked egg quarters to each part. Turn into bowl. Add nuts, mixing well. Refrigerate 30 minutes. On sheet of wax paper or foil, shape pate mixture into a mound. Wrap the pate mound and refrigerate it overnight. Serve pate on platter surrounded by salted crackers. Makes 2 1/4 cups or enough to spread 54 crackers.