Hanger Steak with Marchand de Vin (Wine Merchant) Sauce from Planet Barbecue by Steven Raichlen

Ingredients

• 3 cups dry red wine, such as Burgundy
• Coarse salt (kosher or sea) and freshly ground black pepper
• 1 large mushroom, finely chopped (optional)
• 1 tablespoon extra-virgin olive oil or vegetable oil
• 1½ pounds hanger steak, trimmed
• 1 cup beef stock, preferably homemade
• ½ teaspoon cornstarch
• 2 to 3 shallots, finely chopped (about ½ cup)
• 1 clove garlic, minced
• ¼ cup fresh flat-leaf parsley, finely chopped
• 3 tablespoons unsalted butter, at room temperature
• 1 strip bacon, cut crosswise into ¼-inch slivers