- Cook Soba according to packet instructions, Drain, then rinse in cold water.
- Combine soy and mirin, toss through noodles.
- Brush tuna with oil, then season. Heat a large, non-stick fry pan over high heat. Cook tuna for 20-30 secs each side until lightly coloured but still completely rare inside. Remove from pan and cut into 55mm thick slices.
- Divide the noodles among plates, top with spinach, broccolini and tuna.