Preheat oven (electric cooker: 200 °C/circulating air: 180 °C/gas: see manufacturer). Wash sweet potatoes thoroughly and cut in half lengthwise. Use a knife to make a diamond-shaped incision as deep as possible without cutting through the sweet potatoes. Mix 4 tbsp. Sriracha, 2 tbsp. oil, vinegar and honey. Brush the cut surfaces of the sweet potatoes with it, season with salt and spread on a baking tray with the cut surfaces facing upwards. Bake in a hot oven for about 30 minutes.
In the meantime squeeze the lime. Peel the cucumber, halve it lengthwise and scrape out the seeds. About 1⁄3 Cut cucumber into small cubes. Cut avocados in half, remove seeds and peel the flesh. Blend the rest of the cucumber, avocado, wasabi and 2 tbsp lime juice with a hand blender. Season to taste with salt and pepper.
Rinse fish, pat dry, spread with 3 tablespoons of Sriracha and season with salt. Heat 2 tablespoons of oil in a frying pan, fry the fish on each side for about 2 minutes. Remove the pan from the heat and allow the fish to rest briefly.
Wash coriander, shake dry, pluck off leaves. Pluck fish fillets into large pieces with two forks. Arrange potatoes, dip and fish. Sprinkle with cucumber cubes and coriander and sprinkle with the rest of the lime juice.