Preheat the oven to 200°C on a fan forced setting.
Add the sweet potato chips to a baking tray and drizzle with olive oil. Place the tray in the oven and bake for 20 minutes.
After this time, remove the tray and add the whiting fillets. Return the tray to the oven and leave to cook for 15 minutes.
In the meantime, prepare the salad by combining the mixed lettuce, cherry tomatoes, cucumber and olive oil.
Make the tartar sauce by mixing the Greek yoghurt, Dijon mustard, diced pickle, fresh dill and lemon juice in a small bowl.
Once cooked, plate up the sweet potato chips and fish. Add the salad alongside them.
Serve with the homemade tartar sauce.