Never fail fudge

This recipe comes from Edna Brock and Vernetta Ogden, two beloved women from my home church and two awesome bakers!  

Fudge was a favorite of grandma's, though we can't seem to find her recipe.

Place 10 large marshmallows and 1 stick butter in the top of a double boiler.  Heat over simmering water until melted.  In a separate saucepan, mix together 3/4 c evaporated milk and 2 c granulated sugar and boil for 2 minutes.  Place 1.5 c chocolate bits, 1 tsp vanilla, and 1/2 c chopped nuts in a heatproof bowl.  Combine both cooked mixtures and pour over the chocolate mix.  Beat slightly, and pour into a buttered dish to cool.