You can adapt quantities and ingredients, just keep the proportions. I used butter but the original used marge.
Combine ingredients, dry then liquids.
Mix well and press firmly into flat baking tray(s)
Bake for 20 minutes at 200°C, or until golden brown.
Allow to cool a little and slice while still warm. Separate when cold.
Freezes well!
The recipe was one used in the Iona Abbey Coffee House in the 1970s.