In a stockpot over medium heat, pour the olive oil. When the oil is hot, add the scallions, the garlic, and the ginger.
When the garlic is very fragrant, add the mushrooms cut into slices, the carrot cut into thin slices and the clams. Cook for a couple minutes.
Pour the soy sauce, the sesame oil, the sriracha drops and the water. Let it simmer for 20 minutes until the carrot is soft and the broth has a brownish color. Take the soup out of the stove. Now that the broth is not boiling anymore add the miso paste and season with salt and pepper to taste.
Heat a small pot with water and take it to boil. Pour the soba noodles into the boiling water for 3 minutes. Rinse with cold water.
Serve the noodles and cover with the miso soup. Garnish with seaweed, scallion and sesame seeds.