Hot Fudge Sauce

1/2 c butter
3 1-oz squares unsweetened chocolate
1 c sugar
1/2 c brown sugar
1 c heavy whipping cream
1 t vanilla

Combine butter and chocolate in saucepan. Cook, stirring constantly, over medium heat, until chocolate is melted and mixture is smooth. Stir in sugars. Add cream and bring to boil over medium high heat. Reduce heat and simmer 5 minutes, stirring frequently. Remove from heat and stir in vanilla.