Preheat oven to 500 degrees F (260 degrees C).
Remove stems from Shiitake Mushroom (6 ounce) and discard. Slice into quarter inch thick pieces, and set aside.
Remove touch ends of Asparagus (8 ounce) and discard ends.
Quarter Shallot (1) and Fresh Ginger (0.5 ounce), and reserve for dashi preparation.
Thinly slice Scallion (2) on the bias, and reserve for garnish.
Cut radishes into thin slices. Stack slices and then slice into thin matchsticks. Hold for garnish with green onions.
In a medium bowl, combine Tamari Soy Sauce (1/4 cup), Mirin (1 tablespoon), and White Miso Paste (1 tablespoon). Whisk until smooth.
Pat Chilean Sea Bass Fillet (2) dry with paper towels and slice each fillet in half across to create four even pieces. Place in plastic bag.
Add marinade to bag and gently massage to coat fish. Set aside.
Juice Lime (1/2) into a small bowl. Whisk the Mayonnaise (1 tablespoon) and Togarashi Chili (1 tablespoon) until well combined. Place in refrigerator until plating.
In a medium saucepan over medium heat, bring four cups of water to a boil.
Stir in Bonito Flakes (1 1/2 cup), Seaweed (1/4 cup), Kombu (1 piece), ginger , shallot, Garlic (1 clove), Rice Vinegar (1/4 cup), Tamari Soy Sauce (2 tablespoon), and Mirin (1 tablespoon). Simmer for 10 minutes.
Decrease heat to medium low and simmer for an additional 10 minutes to allow flavors to blend.
When finished, remove from heat, strain broth into a bowl, discard solids, place broth back into pot and hold warm until plating.
Remove fish from marinade and place on foil lined sheet pan. Drizzle remaining marinade over each piece of fish and discard bag.
Roast in the oven for 8 minutes until fillets are fork tender and caramelized. Remove from oven and hold until plating.
While fish is roasting, heat Oil (1 tablespoon) over medium heat in a large saute pan.
Add shiitake mushrooms and a half teaspoon salt and cook for three minutes, stirring often.
Remove mushrooms from pan. To the same pan, add half a teaspoon oil and asparagus with Unsalted Butter (1 tablespoon) and cook for 2 minutes.
Add Unsalted Butter (1 tablespoon) and cook for one minute. Remove from heat and hold for plating.
In two shallow bowls, arrange asparagus in a single layer. Spoon mushrooms over the asparagus. Stack two pieces of sea bass and place over mushrooms. Place a small dollop of togarashi mayonnaise on top of sea bass.
Garnish with Radish (2) and sliced green onions. Pour a quarter cup of dashi around the bottom of the bowl carefully. Serve extra broth on the side.