Remove the steak from the fridge 30-60 minutes before cooking. Heat the barbecue to hot or a chargrill pan on the stovetop over high heat.
For the salsa, toss spring onions in a teaspoon of the oil and season with a pinch of salt. Place on barbeque or in the pan and cook until charred and softened. Remove and cool slightly before roughly chopping and mixing with the avocado, chilli, lime zest and juice, a little more salt and paprika and a tablespoon of olive oil.
Drizzle another splash of oil over the steak and season with salt and pepper and coriander. Grill for 3-4 minutes on each side, turning a few times for a nice even cook (medium–rare). Rest for 5 minutes.
Cook the corn street tacos in a dry pan on a medium heat for 1 minute on each side. Keep warm in a clean tea towel while cooking the rest.
Finely slice steak against the grain. Fill tacos with meat and top with salsa and little extra paprika and salt.
