Soak sea palm and shiitake separately in tepid water for 20 minutes. Drain Palm fronds and Pressure cook ten minutes in water to cover. Drain, cool, set aside. Cook noodles al dente, drain, rinse with cold water, set aside in drainer. Preheat oven to 400°.

Sauce:Remove stems and dice mushrooms; place in saucepan with soaking water and one cup water, rice vinegar and sea salt. Bring to boil, cover and simmer 10 minutes. Puree tahini with 1/3 cup hot stock and return to saucepan. Stir. Dissolve kuzu with 1/4 cup cold water and add to sauce, stirring constantly. Add dill, stir until thickened, remove from heat. Mix noodles, palm fronds and sauce together and place in baking dish. Mix mochi with 1/2 cup water and 1 Tbsp. shoyu, and sprinkle over noodles. Cover and bake 15-20 minutes until mocha is melted and lightly browned. Serve hot.