1 tsp dried chilli flakes (optional)
2 tbsp roughly chopped coriander, to serve
1 sweet onion, thinly sliced
100g/3陆oz dried wakame
4 spring onions, thinly sliced
250g/9oz sushi rice
2 tsp runny honey
salt
2 tsp toasted sesame oil
25g/1oz white sesame seeds
25g/1oz black sesame seeds
2 tsp soy sauce
500g/1lb 2oz raw sashimi-grade fresh tuna, cut into 2.5cm/1in cubes