Uni Spoonbread with Buttermilk Dashi

Name: Uni Spoonbread with Buttermilk Dashi
Cuisine: American
Ingredients: 3 ounces Osetra caviar; 3 pieces sea urchin (uni) per serving; 1½ ounces Jamón Ibérico, cut into brunoise; 3 tablespoons chives, thinly sliced; ½ cup buttermilk; 3 small pieces Jamón Ibérico fat; 2 cups water; 1 piece kombu, 2 inches wide; 1 clove garlic, sliced; ¼ cup hondashi granules; 2 teaspoons grapeseed oil; 2 shallots, thinly sliced; ½ cup grapeseed oil; Salt, to taste; ½ cup ponzu; ½ teaspoon Dijon mustard; Buttermilk Dashi; Caviar and Jamón Ibérico Topping; Caviar and Jamón Ibérico Topping; Ponzu Vinaigrette; Spoonbread; Radish sprouts, as needed; Nasturtium leaves, as needed (if available); Scallions, green part only, cut on the bias; 3 pieces sea urchin (uni) per serving; ¼ cup shallots, sliced; 2 eggs, separated; 2 thin slices from the tip of a jalapeño pepper; 1 small clove garlic, sliced; ½ teaspoon salt