In a large saucepan, mix sugar, butter and milk over medium heat. Stirring occasionally, melt and bring to a boil.
Let the mixture boil for 5 minutes. Remove from heat. Add the vanilla and then whisk in the pudding until mixture is smooth. Stir in the oats. Mix in the crushed Oreos.
Drop by spoonfuls onto a cookie sheet lined with wax paper. Let the cookies cool before removing from the wax paper. Can be stored at room temperature or in the refrigerator.