In large saucepan stir together sugar and cocoa. Stir in milk, add butter. Cook over medium heat, stirring constantly, until mixture comes to a full boil. Boil for 1 minute, stirring constantly.

Remove saucepan from heat, stir in peanut butter and vanilla. Stir in oats. Drop by rounded teaspoon onto waxed paper. Cool for 5-6 hours or until firm