What is the best way to break up a recursive function that is using a ton of resources

For example:

function do_a_lot(){

   //a lot of code and processing is done here
   //it takes a lot of execution time

   if($true){

      //if true we have to do all of that processing again
      do_a_lot();

   }

}

Is there anyway to make the server only have to take the brunt of the first execution and then break up the recursion into separate processes? Or am I dreaming?