This is a favorite as I always seem to have the ingredients on hand, and makes the most amazing, soft and chewy brownies.
Heat oven to 350°
Grease and flour bottom of a square baking dish.
In a large saucepan, melt butter and chocolate over low heat, stirring constantly.
Remove from heat, cool slightly.
Stir in sugar. Beat in eggs, one at a time.
Stir in remaining ingredients.
Spread in pan. Bake for 20-25 minutes (just until set.)