Preheat your oven to 190c
In a large bowl, whisk together the flour, salt, sugar and baking powder.
Now, add the butter/margarine and gently rub this into the dry mixture until you have breadcrumb texture
Now add the raisins, distributing through the mixture using a wooden spoon
Add the egg replacer and stir thoroughly until the mixtures starts to clump together
Add a tablespoon of milk and keep gently mixing until the clumps get bigger and are sticking to the back of the wooden spoon. If you can pick up a clump and it adheres, then you're ready to do!
Now, older recipes say to drop forkfuls of the mixture onto your baking sheet, but I prefer to pinch off large hunks (about the size of a satsuma) and drop them onto the sheet like that.
You should get between 10-12 rock cakes from the mixture. No need to flatten them down.
Bake for about 25 minutes or until light golden brown.
Remove from oven, let cool for 5 minutes on the baking sheet, then remove to a cooling rack.