In a very large bowl, you may even need a bucket. Mix together salt, flour, cream of tarter and oil. Add in boiling water and mix. Be careful not to burn, the mixture will be extremely hot. Mix with a spoon until cool enough to work work. Roll out onto a surface and knead until soft and combined.To make it easier you can knead this in batches. Add in food colouring and knead through. Cut into smaller batches and store in airtight bags or containers.