2) Mix the chilli powder with the salt and then sprinkle the spices all over the fillets and rub in well with your hands. Lay the fillet on the prepared pan, tucking the thin narrow tip of the fillet under so the meat is the same general thickness all the way down.
3) Grill the fillet until golden brown on one side, about 5 minutes. Turn and continue to cook on the other side, until brown, about 5 to 7 minutes more. Remove from the grill, tent loosely with foil and set aside to finish cooking.
4) Leave to rest for 5 minutes. Slice and serve with creamed corn.
For the creamed corn:
1) Shear the corn kernels from the cobs with a knife and transfer the kernels to a bowl. Working over a bowl, run the knife along the cobs to press out the milky liquid. Discard the cobs.
2) Slice the spring onions, both white and a few centimetres of the green, into thin rounds. Separate the spring onion whites and greens.
3) Melt the butter in a medium pan over a medium-high heat. Add the spring onion whites and cook until softened, about 1 to 2 minutes. Add the corn, water, and salt, bring to a simmer, cover and cook until tender, about 2 minutes.
4) Add the cream, bring to a boil, and cook uncovered until slightly thickened, about 1 minute more. Stir in the spring onion greens and tomatoes, season with black pepper and serve.