Argan oil is a nutty-flavoured oil that is produced from the kernels of the argan tree, native to Morocco. Substitute hazelnut or walnut oil. Roasting the beetroot over rock salt helps to retain its natural flavour.Argan oil is a nutty-flavoured oil that is produced from the kernels of the argan tree, native to Morocco. Substitute hazelnut or walnut oil. Roasting the beetroot over rock salt helps to retain its natural flavour.