1½ pounds top sirloin steak, cut into 2-to 3-inch pieces
¼ cup soy sauce
2 tablespoons balsamic vinegar
2 tablespoons minced garlic
1 tablespoon grated fresh ginger
1 teaspoon kosher salt, divided
¼ teaspoon ground black pepper
2 tablespoons olive oil
4 tablespoons unsalted butter, divided
1 medium red onion, cut into wedges
1 pound fresh shiitake mushrooms stemmed and quartered
1 tablespoon chopped fresh cilantro
Instructions
In a heavy-duty resealable plastic bag, combine steak, soy sauce, vinegar, garlic, ginger, ½ teaspoon salt, and pepper. Seal bag, turning to combine. Refrigerate for at least 1 hour or up to 4 hours.
Remove steak from bag, reserving marinade. Pat steak dry with paper towels.
In a 12-inch cast-iron skillet, heat oil over medium-high heat. Add steak to skillet in a single layer; cook until browned, 2 to 3 minutes per side. Remove steak from skillet.
Melt 2 tablespoons butter in skillet over medium heat. Add onions, mushrooms, and remaining ½ teaspoon salt; cook, stirring occasionally, until mushrooms are browned and onion is softened, 5 to 7 minutes. Stir in reserved marinade; boil for 1 to 2 minutes. Stir in remaining 2 tablespoons butter, cilantro, and steak; cook, stirring frequently, until butter is melted and steak is heated through. Serve immediately.
Recipe by Southern Cast Iron at https://www.southerncastiron.com/balsamic-glazed-steak-tips-mushrooms/