This recipe is from Shirley McNevich's Mom's Best Recipes Vol 5. Published here with her permission.
Don't forget to check Shirley's blog.
(by Shirley McNevich)
3 cups Nestle's semi-sweet chocolate bits
4 TBSP butter
1 - 14oz. can Eagle brand condensed milk (NOT evaporated)
1 1/2 tsp. vanilla
dash of salt
3/4 cup chopped nuts (optional)
1 - 7oz. jar Fluff marshmallow OR 2 cups mini marshmallows
In a saucepan over low heat add 2 TBSP butter, chocolate bits, condensed
milk, vanilla and salt--stir until melted and smooth. Remove from heat--add
nuts and stir. Pour mixture into butter-greased 8" or 9" square pan. In a
separate saucepan over low heat add 2 TBSP butter and your choice of
marshmallow--stir and heat until melted and smooth. Pour marshmallow
mixture evenly over the top of the fudge in the pan. Use a table knife to swirl
the marshmallow mixture into the fudge (marbled). Cool completely, then
refrigerate until firm before cutting into squares.