I will admit to cheating here: I buy the pre-peeled, pre-cooked shrimps to save myself the trouble, but you could just as easily clean and cook your own shrimp if you so desire. This is Alton Brown's recipe.
1 (14 1/2-ounce) can diced tomatoes, drained
1/2 cup prepared chili sauce
4 tablespoons prepared horseradish
1 teaspoon sugar
Few grinds fresh black pepper
1/2 teaspoon kosher salt
1 tablespoon olive oil
Sprinkle Old Bay seasoning
Combine all ingredients in a food processor and blend until smooth. Refrigerate until ready to serve.