Heat sugar, butter, milk and cocoa in a large pot and heat to a boil. Boil for one minute (not 45 seconds, not 75 seconds, exactly one minute). Remove from heat and add vanilla.
Pour mixture over your oatmeal and mix well. Drop by spoonfuls on waxed paper. Store in an airtight container.
Recipe by Nifty Mom at https://niftymom.com/2013/03/nutella-cookies/