olson's old fashioned chocolate sauce

1 c. butter

12 oz. package of semisweet chips (2 cups)

4 c. powdered sugar

2 cans evaporated milk

2 tbsp. vanilla

Melt butter and chips in large saucepan. Add sugar and milk. Stir and bring to a boil. Boil 8 minutes stirring constantly. Remove from heat and add vanilla.