Donna Hay's fast, fresh, simple Steak and Three Veg.
Preheat oven to 200°C (400°F).
To make the three veg, place the potato, sweet potato and parsnip in separate bowls.
Divide the butter, parmesan, thyme, salt and pepper among the bowls and toss to combine.
Line a baking tray with non-stick baking paper.
Pile each vegetable into 2 flat piles. Bake for 20–25 minutes or until golden and crisp.
While the vegetables are cooking, cook the beef.
Sprinkle the beef generously with salt and pepper.
Heat a frying pan over high heat.
Cook the beef for 3 minutes each side or until well browned.
Place on a baking tray and bake for 4 minutes for rare and 7–8 minutes for medium.
To serve, slice the beef in half and place on serving plates with the three veg. Serve with aïoli.