Line 15x10x1-inch baking pan with foil, extending foil over sides of pan; grease foil. In large saucepan, combine sugar, butter and evaporated milk; cook and stir over medium heat until sugar is dissolved. Bring to a full boil, stirring constantly. Boil uncovered over medium heat without stirring for 5 minutes.
Remove saucepan from heat. Add marshmallows; stir until melted. Add chocolate chips, sweet chocolate and unsweetened chocolate, stirring constantly until all chocolate is melted and mixture is smooth. Stir in vanilla, almond extract and walnuts. Quickly spread mixture in greased foil-lined pan. Sprinkle with colored sugar. Cool 1 hour or until completely cooled.
Remove fudge from pan by lifting foil; remove foil from sides of fudge. With long knife, cut fudge into squares.