Cook the snow peas in a saucepan of boiling water for 1 minute. Drain, then put into a bowl of iced water for 2 minutes. Drain well and combine with the sprouts and capsicum in a serving bowl.
Dissolve the dashi granules in 1½tablespoons of hot water. Whisk in the soy sauce, mirin, sugar, garlic, ginger, oils and half of the sesame seeds. Pour over the salad and toss to combine. Season, and serve sprinkled with the remaining sesame seeds.