Cook and drain the beetroot, cubed beetroot will take around 20 minutes to cook in boiling water. Alternatively, use vacuum-packed cooked beetroot.
Put all the ingredients in a food processor and whizz until smooth. Put one serving in a sealed container to take to work, chill the remainder in the fridge - it will keep for four days, or freeze for up to three months.
Pack the oatcakes, rocket/arugula and spring onion/scallion to take with you.