Flecks of grated lime peel permeate this tangy vinaigrette, adding splashes of citrus to every bite. To reduce the sharpness of the red onion, rinse it under cold water before dicing.

VINAIGRETTE
1/4 cup lime juice
2 teaspoons grated lime peel
2 teaspoons honey
2 teaspoons ground cumin
2 teaspoons Dijon mustard
1/2 teaspoon salt
6 tablespoons canola oil
2 tablespoons chopped cilantro

TOSTADAS
4 (6-oz.) halibut fillets (1 1/4 to 1 1/2 inches thick)
1 tablespoon canola oil
1/4 teaspoon salt
1/8 teaspoon freshly ground pepper
4 tostada shells
4 cups shredded romaine lettuce
2 large tomatoes, diced
1/2 cup diced red onion, divided
1 mango, chopped
1 avocado, chopped
2 tablespoons chopped cilantro

1. In small bowl, whisk together all vinaigrette ingredients except oil and cilantro. Slowly whisk in 6 tablespoons oil; stir in 2 tablespoons cilantro.

2. Heat grill. Brush halibut with 1 tablespoon oil; sprinkle with 1/4 teaspoon salt and pepper. Place on gas grill over medium-high heat or on charcoal grill 4 to 6 inches from medium-high coals; cover grill. Grill 6 to 8 minutes or until halibut just begins to flake, turning once.

3. Meanwhile, microwave tostada shells on high 40 seconds or until warm. Top each with one-fourth of the lettuce and tomatoes and 1 tablespoon of the onion. Top with halibut; sprinkle with mango, avocado and remaining onion. Drizzle with vinaigrette; sprinkle with 2 tablespoons cilantro.