Prepare 9" x 9" pan by greasing lightly with butter. I line mine with parchment paper and lightly grease it with butter.
In sauce pan combine butter, sugar, marshmallows and heavy cream. Bring to boil over medium heat stirring constantly till it comes to a boil. Continue to boil for 5 minutes stirring often.
After boiling the mixture add vanilla chips and still till they are completely melted. Stir in vanilla and nuts. Pour fudge into the 9" x 9" prepared pan. Let cool completely and cut into desired sized pieces and store in air tight container in the fridge. Take fudge out of the fridge 30 minutes before serving.
For variation in this recipe, replace vanilla with 2 tsp maple flavoring for maple fudge. You can also replace the nuts with 1/2 cup chopped and drained maraschino cherries and than you have Oprah fudge.