Instructions

In a large shallow dish, combine flour, 1/2 teaspoon salt and pepper. Pat beef dry with paper towels. Add beef to dish, 1 piece at a time; turn to coat.
Select saute setting on a 6-qt. electric pressure cooker and adjust for medium heat. Add 1 tablespoon butter and 1-1/2 teaspoons oil; brown 3 beef shanks. Remove from pressure cooker; add 1/4 cup wine, stirring to loosen browned bits. In a large bowl, combine tomatoes, broth, vegetables, seasonings and remaining salt. Return browned beef shanks to cooker; pour in half of tomato mixture.
Lock lid; close pressure-release valve. Adjust to pressure-cook on high for 40 minutes. Allow pressure to naturally release for 10 minutes, then quick-release any remaining pressure. Remove meat and vegetables from pressure cooker; keep warm. Make second batch with remaining ingredients, repeating previous procedure. Press cancel.
After removing all meat and vegetables, discard bay leaves. Skim fat from cooking juices. Select saute setting and adjust for medium heat. Bring to a boil. In a small bowl, mix cornstarch and water until smooth; stir into cooking juices. Return to a boil, stirring constantly; cook and stir until thickened, about 2 minutes. Press cancel.
In a small bowl, combine gremolata ingredients. Serve beef with gremolata and sauce.