1. Place the veal, smooth side down, on a cutting board. Inspect for thickness. The whole piece should be about 1” or less thick. If there are any very thick areas, use a mallet to pound thin. Because of the breakdown of muscles on veal breast, some parts will respond to pounding, some will not. If, after pounding, some areas are still too thick, either trim them off or, if they are close to the edge of the piece, filet them open so they stay connected to the meat like a flap. Season with salt and pepper and refrigerate 24 hrs.
2. Preheat the oven to 250F.
3. Combine the breadcrumbs, cheeses, spinach, and garlic in a large bowl and toss to combine. Remove the veal from the fridge and place on a sheet tray, smooth side down. Spread the sausage evenly over the meat, staying within about 1” of the edges (it will fill in this area as we roll it). Repeat with the breadcrumb/cheese mixture. Roll the veal up into a cylinder and tie tightly with twine.
4. Brown the veal on all sides in a large dutch oven over high heat. Lower the heat to medium and continue to brown until the color is rich and dark, just short of burning. Remove the veal, add the tomato sauce and chicken stock and bring to a simmer. Return the veal to the pot, cover, and place in oven until tender, about 3-5 hours. Remove and uncover the pot and let cool about 1 hour, then place the entire pot in the fridge.
5. The next day, preheat the oven to 375. Remove the veal from the pot and trim off the string. Slice into 1.5” slices. Place the pot over medium heat and bring the contents to a simmer to keep warm. Meanwhile, heat a large cast iron skillet over medium high heat. Pour about 1 tbsp olive oil in the pan and brown the veal pieces on a single cut side, working in batches so as not to overcrowd the pan. Place the veal pieces, brown side up, on a tray and roast until heated thru, about 10 minutes.
6. When veal is done, remove the pot with the tomato-braising sauce from heat and finish with the basil, parsley, and ¼ cup parm. To serve, spoon about ½ cup of the sauce onto the bottom of a wide bowl. Place veal on top, drizzle with olive oil and grate a little lemon zest on top. Top with a few leaves of farmers market arugula tossed with lemon juice, olive oil, and the remaining parm.