A smoky pate that's a cinch to prepare can be a quick, at-the-ready course for guests to enjoy when they arrive. A drizzle of the tomato juices gives the creamy dip an acidic boost.
Puree bluefish, cream cheese, and butter in a food processor. Transfer to a bowl, and stir in lemon juice, horseradish, mustard, cayenne, and shallots. Season with salt and pepper. Cover, and refrigerate for up to 2 hours.
Preheat oven to 300 degrees. Oil a rimmed baking sheet. Toss tomatoes, salt, pepper, garlic, and thyme, and arrange tomatoes cut sides down on baking sheet. Bake until shriveled and starting to brown, about 1 1/4 hours. Let cool completely. Transfer tomatoes and juices to a serving dish.
To serve, spread pate on crackers, top with a roasted tomato half, and drizzle with juices.
If you can't find smoked bluefish, substitute another mild smoked fish, such as trout. Bluefish can be found online or in specialty food markets.