Pour boiling water over the pasta and let it swell for 4-6 minutes according to the instructions on the packet or in the water. Roast sesame seeds in a pan without fat and remove.
Mix soy sauce, lime juice, pepper and 2 tablespoons of brown sugar. Fold in the oil. Drain noodles, rinse briefly and drain well. Mix with the lime sauce.
Clean and wash the zucchini. Peel onions. Cut both with a spiral slicer into long "spaghetti". Wash and halve the tomatoes. Wash and shake coriander dry, pluck off the leaves and chop coarsely.
Fold everything under the noodles. Season again with salt, sugar and Sriraha sauce to taste. Sprinkle with sesame seeds. Garnish with lime slices if desired.