1. In a large bowl, combine the ground beef, 1/2 cup Bloody Mary mix, 1/4 teaspoon celery seed, egg, salt and pepper. Mix, then form into 6 evenly sized burgers. Set aside.
2. In small bowl, combine all of the ingredients for the Bloody Mary ketchup. Set aside.
3. Place a large skillet over medium-high heat. Add 1 tablespoon of vegetable oil followed by the burgers. You may work in 2 batches if you don't have enough room in the skillet for all 6 burgers.
4. Cook the burgers on one side until browned, about 4 minutes, then flip and cook to your desired doneness, about 4 minutes more for medium. Transfer the burgers to a plate to rest for 3 minutes.
5. Place each burger on a bottom bun and top with an even amount of Bloody Mary ketchup followed by an onion slice and an even amount of crumbled blue cheese.
6. Place the top bun on the burger. Serve each burger with 2 pickles, 2 olives and a celery stick.