In a mixing bowl, combine the garlic, parsley, onions, capers, salt, cayenne, and lemon juice and rub. Using a fork, mash and stir the ingredients in the bottom of the bowl to extract all of the flavors. Let sit for about 2 minutes. Add the crabmeat, mustard, mayonnaise, and ketchup. Toss gently but thoroughly. Refrigerate for at least 1 hour.
Yield: 4 first-course servings