Preheat the oven to 200 degrees Centigrade/Gas Mark 5
Line a baking sheet with parchment
Place the flour, baking powder, caster sugar and salt into a food processor, add the dairy-free margarine and pulse until it is all combined (or rub in with your fingertips until it resembles breadcrumbs)
Pour in the oil and pulse again.
Pour in the water and pulse until it forms a ball of dough.
Turn onto a floured surface and roll out until about 3-5mm thick
Cut out any shapes you like, fluted circles are classic.
Place, well spaced on the baking sheets and pick with a fork.
Bake for 10-12 minutes until starting to turn golden
As soon as you remove them from the oven, brush with the oil and sprinkle with salt.
These keep well for a few days in a sealed container.