How to Make It
Bring a large pot of salted water to a boil. Add the shrimp, cover, and bring back to a boil. Continue boiling, partially covered, until the shrimp are just done, 1 to 2 minutes. Drain. Let the shrimp cool and then peel them.
In a large glass or stainless-steel bowl, combine the lemon juice with the olive oil, tomato, salt, pepper, and parsley. Add the shrimp and toss.
• Substitute a pound of sea scallops for the shrimp. Heat one tablespoon of oil in a large nonstick frying pan over moderately high heat until very hot. Season the scallops with one-eighth teaspoon salt. Put the scallops in the pan and sear until brown on the bottom, one to two minutes. Turn and brown on the other side until just done, one to two minutes longer. Remove the scallops and cut them into quarters. Toss with the marinade.
• Spice up the dish by adding one-quarter teaspoon dried red-pepper flakes to the marinade.
• Use chopped fresh basil instead of the parsley.
• For an extra flavor dimension, add a clove of minced garlic to the marinade.