Preheat an oven to 200C.
Combine all the tartare ingredients in a bowl and season to taste. Set aside in the fridge.
Combine the flour mix ingredients and place in a shallow bowl.
Whisk the eggs and milk together and place in another bowl.
Toss the fish in the flour then in the egg mix and back in the flour mix. Pressing it on well. You want a good coating. Set aside
Toss the sweet potato in the oil and season with salt and pepper. Roast on a baking tray for 15 minutes.
Place the fish on a separate lined baking tray and bake for 10-12 minutes carefully flipping halfway.
Serve the fish with the sweet potato, tartare sauce and lemon.