Grilled Yellowtail with Miso Sauce - Andrew Zimmern

Ingredients

• 1 cup Japanese blond miso
• 1 teaspoon instant dashi powder
• 1/2 cup sake
• 3 egg yolks
• 1/4 cup plus 3 tablespoons sugar
• 2 sticks salted butter, softened
• 1 large shallot, roughly chopped
• 1 garlic clove, sliced
• 1 cup shiso leaves
• 1/4 cup garlic chives or chives, chopped, plus more for garnish
• 2 tablespoons lemon juice
• 2 teaspoons olive oil
• Kosher salt
• Freshly ground black pepper
• 2 medium white onions, peeled and halved crosswise
• 12 red radishes, trimmed
• Neutral oil, for brushing
• 4 yellowtail fillets or portions, skin removed
• Neutral oil