Vietnamese Tuna Seviche

Ingredients

• 3 tablespoons Asian fish sauce (nuoc nam)
• 2 1/2 tablespoons sugar
• plus more for sprinkling
• 1 1/2 tablespoons water
• 1 tablespoon fresh lemon juice
• 1 tablespoon fresh lime juice
• 1 small garlic clove
• minced
• 1/2 teaspoon minced fresh ginger
• 1 serrano or Thai chile
• thinly sliced
• with seeds
• 1 cup yellow cherry tomatoes
• halved
• 1 tablespoon soy sauce
• 1 tablespoon rice vinegar
• 1/2 pound cold sushi-grade tuna
• cut into 1/2-inch cubes
• 1/2 pound yellow seedless watermelon
• cut into 1/2-inch cubes
• 2 tablespoons tobiko (flying-fish roe)
• 2 tablespoons torn purple or green basil leaves

Instructions

1. In a small bowl, stir the fish sauce with 2 1/2 tablespoons of the sugar, the water, lemon juice, lime juice, garlic, ginger and the sliced chile.
2. In another small bowl, toss the tomatoes with the soy sauce, vinegar and a pinch of sugar and let stand for 5 minutes.
3. In a medium bowl, gently toss the tuna and watermelon with the dressing.
4. Using a slotted spoon, transfer the salad to 4 plates, allowing as much dressing as possible to drain back into the bowl.
5. Using the slotted spoon, arrange the tomatoes on the plates.
6. Garnish the salads with the tobiko and basil and serve right away.