Heat oil in a medium nonstick skillet over medium high heat. Season veal shanks with salt then sear all four sides until browned but not cooked through. Add to the insert of a slow cooker.
Then add the onion, celery, carrots, garlic, tomato paste, crushed tomatoes, beef broth, black pepper, thyme, and rosemary. Stir to mix a bit.
Cover and cook on high for 4 hours or low for 8 hours. Discard sprigs of thyme and rosemary. Sprinkle fresh parsley on top prior to serving, if desired.