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This Grilled Flank Steak With Onions relies on simple, everyday ingredients such as flank steaks, vinegar, salad oil and brown sugar. It comes together quickly and makes 4 servings, at about 748 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.
It's versatile enough for an easy weeknight dinner yet satisfying enough for guests at the weekend. Serve it with your favorite sides, and keep any leftovers for a quick meal the next day.
Updated Jun 30, 2026