In a small mixing bowl mix the soy sauce and sesame oil and brush the nori sheets generously with this mix. Place nori sheets onto baking trays and bake in oven for 10-15 minutes or until the sheets become crunchy. Remove and cool completely.
Meanwhile dice the tuna into 4mm cubes using a sharp knife.
Place the cubed tuna into a mixing bowl and add the lime juice and salt. Check for seasoning, adjust if needed. Seasoning will vary depending on time of year and size of limes.
Place the tuna into a serving dish and garnish with sea urchin, pomelo and angel hair chilli. Serve with nori sheets.