Clean and prep the vegetables. Peel and cut the kohlrabies into match sticks. Clean and cut the radish into matchsticks of the same size as the kohlrabi. Cut the spring onion into long pieces.
Heat sesame oil in a pan. When hot add kohlrabi and radish. Stir fry on high. Add the brown sugar, soy sauce, rice wine vinegar and salt. Toss till the sauces coat the vegetables. Be wary of overcooking - the veggies can lose their crunch. Add the spring onion and turn off the heat. Serve hot with some lightly toasted sesame seeds sprinkled on top.