Place noodles in a large bowl and add 1 quart boiling water. Stir to separate noodles and let stand until tender to bite, about 10 minutes. Drain well. Return noodles to bowl.
Meanwhile, trim off discolored mushroom stem ends; rinse caps well. In a heavy plastic food bag, mix soy sauce, sherry, sesame oil, brown sugar, ginger, and garlic. Add mushrooms, seal bag, and turn over to mix. Let stand 10 to 20 minutes, turning over several times.
Lift mushrooms from bag and save marinade. Oven-roast mushroom caps.
To noodles, add rice vinegar, carrots, radicchio, and 1/2 cup cilantro leaves. Add about 2 tablespoons reserved soy marinade, or to taste. Mix well.
Spoon noodle slaw equally into wide bowls. Thinly slice mushroom caps and arrange equally on portions. Garnish with additional cilantro leaves.