Stir together first six ingredients in a 3 quart saucepan over medium-high heat and cook, stirring constantly, until mixture comes to a boil. Continue cooking, stirring constantly, until a candy thermometer registers 234F (soft-ball stage).
Remove pan from heat; stir in remaining ingredients until well blended. Pour into a greased aluminum foil-lined 8-inch square pan. Let stand 2 hours or until completely cool; cut fudge into squares.