Cajun Shrimp Tacos

Yield: 8 servings

Chili Sour Cream
2 cups sour cream
2 teaspoons chili powder
1/2 teaspoon cayenne pepper

Salsa
3/4 pound tomatillos, husks removed, rinsed,
    quartered (about 3 cups)
1/2 cup coarsely chopped unpeeled green apple
    (such as Granny Smith)
2 tablespoons coarsely chopped fresh basil
2 tablespoons coarsely chopped fresh mint

Shrimp
1 1/2 teaspoons chili powder
1 1/2 teaspoons paprika
2 pounds uncooked medium shrimp, peeled, de-veined
2 tablespoons olive oil
1 tablespoon minced garlic
16 taco shells
1 large bunch watercress, trimmed
2 avocados, peeled, pitted, cubed

Sour Cream: Whisk all ingredients in medium bowl to blend. Season with salt. (Can be made 1 day ahead.) Chill.

Salsa: Finely chop tomatillos, apple, basil and mint in food processor. Transfer to small bowl. Season to taste with salt. (Can be prepared 6 hours ahead. Let stand at room temperature.)

Shrimp: Combine chili powder and paprika in large bowl. Add shrimp; toss to coat. Let stand 5 minutes. Heat oil in heavy large skillet over high heat. Add garlic and saut? until fragrant, about 1 minute. Add shrimp; saut? until opaque in center, about 5 minutes. Season with salt and pepper. Transfer to a small bowl.

Preheat oven to 350 degrees F.

Arrange taco shells on heavy large baking sheet. Bake until hot, about 8 minutes. Place shells in napkin-lined basket. Arrange half of watercress on platter. Top with shrimp. Chop remaining watercress. Place in small bowl. Place sour cream, salsa, avocados and chopped watercress in separate bowls.