For the steak, place the oil in a hot frying pan, then add the steak. Season and add the banana shallot.
Cook for three minutes on each side or to desired "doneness". Take off the heat and let the steak rest, continue to cook the shallots for a further five minutes till golden and soft.
For the sweet potato, peel and cut the sweet potato into thin chips, Heat the oil in a deep frying pan or deep-fat fryer. (CAUTION: hot oil can be dangerous. Do not leave unattended). Fry the potatoes until golden and crisp. Remove and drain on kitchen paper.
Serve the steak with the shallot and the chips.