I had one of the best steaks EVER in Bologna at Drogheria della Rosa. It was topped with a fabulous balsamic glaze, and the owner, Chef Emanuele, gave me his recipe:
Heat 2 T. olive oil in a skillet. (He cooks the steak here, but Brad grilled ours, and I added the juice from the pan.) Add 1/3-1/2 c. balsamic vinegar. Cook 2-3 minutes until it has reduced and thickened, stirring, constantly. Add 3-4 T. cream, and continue cooking until it has heated through, and the sauce is smooth. Pour over steak and serve immediately.