Heat your oven to 200°C/Fan 180°C/Gas 6. Trim the ends off your parsnips. Peel. Halve them widthways. Halve or quarter the thin ends to make chips. Slice the thick top ends into chips around 1 cm wide each.
Pop the parsnip chips in a bowl. Add a little splash of olive oil. Season with some salt and pepper. Toss to coat. Spread them out on a large baking tray or in a roasting tin. Bung in the oven for 25 mins till the chips are tender and browned.
Peel and grate the garlic and ginger. Halve the chilli. Scoop out the white bits and seeds. Finely chop the chilli. Rinse, dry and finely chop the tomatoes. Pop them all in a bowl.
Finely grate or pare the zest from the lime. Juice it. Stir the lime zest and juice into the tomatoes to make a salsa. Put to one side.
Wash the watercress under cold running water. Gently pat dry with kitchen paper. Pinch out any thick stalks.
Warm a griddle or frying pan over a high heat. Brush the steaks with a little olive oil. When the pan is smoking hot, add the steaks. Fry for 1-2 mins till nicely browned. Flip and fry for 1-2 more mins (or a few mins more for well done).
Pop the steaks on a plate. Cover with foil. Rest for 2-3 mins. Serve the steaks with the chips, watercress and the gingery tomato salsa.