First prepare your dashi broth, which is the base of the soup. Place the konbu and ginger in a large pot filled with 8 cups of cold water and heat over medium high. Right before the water comes to a boil turn off the heat. Let the konbu stand for 6 to 8 minutes to steep.

Return the pot to medium heat, and once again, just before it begins to boil, remove the pot from the heat. Add the bonito flakes and let steep. Once the bonito flakes have sunk to the bottom of the pot, strain through a fine mesh sieve lined with cheesecloth. Set the broth aside.

In a medium saute pan over medium high heat, add the canola oil. When the oil is hot, add the shiitake and cloud ear mushrooms. Saute until the mushrooms are golden and then add the scallions. Cook for 2 minutes, until the scallions are fragrant and wilted. Remove the mushrooms to a plate lined with paper towels.

In a 6 quart stock pot, add the dashi broth and bring to a boil over medium high heat. Reduce the heat and bring the broth to a simmer. Add the miso, tamari and sesame oil, stirring until the miso has completely dissolved. Add the mushrooms to the broth to warm through.

Divide the soba noodles between four bowls, ladle the broth and mushrooms into each bowl and garnish with sliced scallions and a few Enoki mushrooms.