Preheat oven 325° F.
Grease and flour pan, either 9 x 13″ or 8 1/2 x11″. Adjust amounts ofingredients accordingly.
Melt chocolate and butter together in top of a doubleboiler over simmering water. Allowto cool slightly before adding to rest of ingredients.
In large mixer bowl, beat eggs well. Add sugar gradually and beat. Add flour. Then add salt, vanilla and cooled chocolate-butter mixture. Finally, add chopped walnuts to taste, e.g. 3/4 to 1 1/4 cups.
Bake for 50 minutes in a 325° F. Allow to cool somewhat in pan before cutting.