Remove hard stems from spinach, wash well and drain. Place spinach, with only wash water clinging to leaves, in medium saucepan.
Gently cook over medium heat about 10 minutes, or until tender. Remove pan from heat and let spinach cool. Drain and squeeze to remove as much water as possible, then set aside. (Use water in soup, or as desired.)
Heat 3 tablespoons olive oil in saute pan. Add onion and saute until just golden. Remove from heat. Place in large bowl (must hold all filling later on).
Pound out steak slice (or slices) to 1/4-inch thick with mallet or flat side of heavy cleaver. Do not tear meat.
Mix Pecorino cheese, bread crumbs, ground veal and parsley in bowl with sauteed onion. Season to taste with salt and pepper.
Add raw eggs and mix again.
Spread mixture evenly on pounded meat. Place hard-cooked eggs lengthwise, in row, on meat mixture. Scatter cold cuts, cheeses, peas, chopped pork fat and spinach evenly on top of ground-meat mixture and hard-cooked eggs.
Roll meat tightly over stuffing into shape of log and tie with string in several places to secure during cooking
Brown meat roll in large skillet in remaining 4 tablespoons olive oil, turning often.
When meat is browned, place in flame-proof casserole dish. Pour in wine and broth.
Add tomato paste and stir liquids well to disperse paste. Bring liquid to boil, then immediately reduce to simmer.
Finish cooking meat on top of stove at simmer, or in 350-degree oven, 1 1/2 to 2 hours, turning meat often to baste with liquid.
There should be about 1 cup liquid to use as sauce in dish, left in pan when meat is done. Remove meat from casserole, let stand in warm place about 10 minutes, then remove string.
Cut into 1/4-inch-thick slices and serve on heated plates. Spoon on remaining, pan juices.