Ingredients

• 2 teaspoons water
• 1 teaspoon prepared Chinese-style hot mustard or Dijon mustard
• 1/3 cup white miso (fermented soybean paste)*
• 3 tablespoons rice vinegar
• 2 tablespoons mirin (sweet Japanese rice wine)**
• 4 teaspoons sugar
• 1 teaspoon soy sauce
• 4 5- to 6-ounce sea bass fillets
• 8 green onions, trimmed
• Olive oil
• Toasted sesame seeds

Instructions

1. Whisk water and mustard in small bowl until smooth. Combine miso, vinegar, mirin, sugar and soy sauce in small saucepan. Stir over medium heat until smooth, about 3 minutes. Whisk in mustard mixture. (Can be made 1 day ahead. Rewarm over low heat before using.)
2. Prepare barbecue (medium-high heat). Brush fish and green onions with oil. Sprinkle both with salt and pepper. Grill fish until opaque in center, about 4 minutes per side. Grill onions until beginning to brown, about 3 minutes per side. Transfer fish and onions to 4 plates. Spread sauce atop fish. Sprinkle sesame seeds over sauce and serve.
3. *Available at Japanese markets and natural foods stores and in the Asian foods section of some supermarkets. **Mirin is available at Japanese markets and in the Asian foods section of some supermarkets.
4. *Available at Japanese markets and natural foods stores and in the Asian foods section of some supermarkets.
5. **Mirin is available at Japanese markets and in the Asian foods section of some supermarkets.