Served here on plain basmati rice and mango chutney
https://www.bbc.co.uk/food/recipes/spiced_tuna_steak_06873
by Matt Tebbutt
1 tsp toasted coriander seeds
1 tsp toasted cumin seeds
1 bunch fresh coriander stalks, chopped
1 bunch fresh parsley, chopped
½ bunch fresh mint, chopped
1 red onion, finely chopped
1 pinch dried chilli flakes
1 red chilli, finely chopped
1 garlic clove, finely chopped
2 tbsp grapeseed oil
2 limes, juice only
½ tsp salt
1 x 400g/14oz thick-cut fresh tuna steak
To make the spiced tuna steak, blend the coriander seeds, cumin seeds, coriander stalks, parsley, mint, red onion, chilli flakes, red chilli, garlic, grapeseed oil, lime juice and salt together in a blender. Put the tuna in a non-reactive bowl and cover it with the marinade. Cover and leave overnight in the fridge
To serve, heat a drizzle of oil in a frying pan over a high heat and sear the tuna on both sides for a few minutes, but keep it rare in the middle. Slice into chunks and serve.