Mama's Hot Fudge

This simple recipe is the best hot fudge EVER!! You only have to keep stirring it or it will burn and you'll have a pot of gross "chocolate" to eat. YUCK!! And one other thing. If you don't have unsweeted chocolate squares then I am sorry to say but you can't make it then. : /
Here's the recipe:
Ingredients:
* 5 squares of unsweetened chocolate squares
* 1/2 cup of butter
* 1 can of evaporated milk
* 3 cup of powered sugar
* 1 and 1/4th teaspoon vanilla

Directions:
1. Melt chocolate and butter. Add milk and sugar alternatively on medium heat. Bring to a boil.
2. Boil for 8 minutes. You MUST stir constantly and cover all parts of the bottom of the pan. This can get a burnt taste easily.
3. Remove from heat and add vanilla.