Add the grate/shred blade to food processor. Turn machine on and drop in the brussels sprouts to shred. Now drop in the carrots to shred. Alternatively, you can finely chop brussels and shred carrots with a hand-held grater. Transfer to a large mixing bowl.
Stir in the diced apple, celery, sunflower seeds, and raisins into the carrot and brussels sprout mixture.
Add lemon juice, salt, pepper, and optional fresh thyme to taste. Add a small amount of maple sryup (about 1/2-1.5 tsp) to take the edge off the lemon juice. Sprinkle with cinnamon if desired. Serve & enjoy!