Preheat the oven to 325 degrees F.
Pat the meat dry and sprinkle with salt and pepper, then dredge in flour.
In batches, brown the meat in the oil over medium-high heat in a large Dutch oven. Set the beef aside.
Add the garlic, celery root and onions to the beef drippings and season with salt and pepper. Cook until softened, 5 to 7 minutes. Add the tomato paste and stir 1 minute, then add the stock, wine, Worcestershire, beef and herb bundle. Cover and cook in the oven until tender, up to 2 hours. Cool and store for a make-ahead meal. Reheat in a 325 degree F oven until bubbly.
For the celery gremolata: Combine the parsley, celery, anchovies and lemon juice, and dress with the EVOO. Loosely combine with pecorino cheese.
Serve the potted beef in shallow bowls, with the celery gremolata on top. Serve mashed or boiled baby potatoes or crusty bread alongside.