Step 1

Combine mushrooms, ginger, chile, garlic, kombu, turmeric, and 4½ cups water in a medium saucepan. Bring to a simmer over medium-high heat, cover, then reduce heat to very low and cook 25 minutes to infuse broth. Strain dashi through a fine-mesh sieve into a large bowl; discard solids. Wipe out pot, pour dashi back in, and bring to a simmer.

Step 2

Mix miso paste and 1 Tbsp. broth with a spoon or fork in a small bowl to loosen miso. Stir miso mixture and soy sauce into broth; season with salt. Keep hot.

Step 3

Do Ahead: Dashi can be made 2 days ahead. Let cool, then transfer to an airtight container and chill.

Step 4

Heat olive oil in a medium skillet over medium-high. Add mushrooms and cook, stirring occasionally, until golden brown and beginning to crisp, about 5 minutes. Remove pan from heat, grate garlic over mushrooms, and stir to combine (garlic will cook in residual heat of mushrooms). Season with salt.

Step 5

Drop vermicelli into very hot dashi broth. Cover and let sit 3 minutes (or cook according to package directions).

Step 6

Divide noodles and dashi between bowls. Top with mushrooms, radishes, herbs, fermented vegetables, and sesame seeds. Drizzle with hot sauce and sesame oil before serving.