I have been thinking of brewing a porter or a stout but have no knowledge of what actually makes a good porter. I was thinking of making 5 1 gallon batches using goldings hops and varying amounts of chocolate malt, black patent malt and roasted barely to try and understand what each of these speciality grains brings to a beer. Any help on formulating 5 distinct but similar recipes would be much appreciated as I currently have no idea how to go about doing this.