Perfectly Poached Shrimp with Green Goddess Sauce

Ingredients

• 8 fillet oil-packed anchovies canned
• 0.8 cup kosher salt 
• 0.3 cup chives fresh chopped
• 1 cup parsley fresh packed chopped ()
• 3 tablespoons tarragon fresh chopped
• 1 large garlic clove 
• 0.3 cup spring onion chopped (white and pale green parts only)
• 4 pounds shrimp uncooked unpeeled ( 75)
• 2 cups mayonnaise 
• 1 tablespoon rice vinegar 

Equipment

• food processor
• bowl
• pot
• colander

Directions

1. Finely chop garlic in food processor.
2. Add all remaining ingredients; blend until smooth and pale green. Season sauce to taste with salt and pepper.
3. Transfer sauce to serving bowl. Cover and refrigerate until cold. (Can be prepared 2 days ahead. Keep refrigerated.)
4. Fill 2 large bowls with ice water; set aside. Bring very large pot of water to boil over high heat.
5. Add 1/2 cup coarse salt to boiling water; return to boil. Rub shrimp in another large bowl with remaining 1/4 cup salt.
6. Add shrimp to boiling salted water and cook just until cooked through, about 3 minutes (water will not return to boil). Immediately drain shrimp in colander, then quickly divide between prepared bowls of ice water; cool completely.
7. Drain well. Peel and devein shrimp, leaving tails intact. Arrange shrimp on platter. (Can be made 4 hours ahead. Cover and refrigerate.)
8. Serve shrimp with sauce.