Heat oil in a deep-fryer to 140°C or add enough oil to a heavy-based saucepan to reach a depth of 5cm. Heat on medium, until a cube of bread sizzles on contact. Using a sharp knife or mandoline, slice kumara into thin chips. Deep-fry chips in batches for 10-12 minutes, until crisp. Drain on the paper towel and season with sea salt.
To make salsa verde, crush anchovies and garlic in a mortar and pestle to make a rough paste. Add eschalot and lemon rind and lightly pound to release flavors. Stir in capers, herbs and lemon juice, bruising herbs a little. Season well and stir through oil.
Preheat a chargrill on high. Brush steaks with extra oil and season. Cook for 2-3 minutes each side for rare or until cooked to your liking. Remove from pan and rest for 5 minutes.
Top steaks with salsa and serve with chips.
