Mix the oats, coconut, peanuts, and raisins together in a large bowl.
Stir the sugar, milk, butter, and cocoa powder together in a saucepan and bring to a boil; boil for 1 minute and immediately remove from heat. Stir the vanilla into the cocoa mixture; pour over the oat mixture and stir to coat. Scoop heaping tablespoonfuls of the mixture and drop into haystack-like piles onto waxed paper; allow to cool completely before serving.
