Pan-Seared Flat Iron Steak with Balsamic and Rosemary Reduction

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

Juicy flat iron steak pan-seared to medium with a rich balsamic vinegar and fresh rosemary sauce to elevate the beef’s natural flavor. This Mediterranean-inspired beef recipe, ready in about 25 minutes, pairs flat iron steak, salt, black pepper for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 420 calories and feeds 3, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 10 min Cook: 15 min Serves 3 Mediterranean cuisine 420 cal/serving
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Ingredients

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Instructions

  1. Step 1: Season 1.25 pounds flat iron steak generously with 1 teaspoon salt and 1/2 teaspoon black pepper on both sides.
  2. Step 2: Heat 2 tablespoons olive oil in a heavy skillet over medium-high heat until shimmering. Add the steak and cook for 5 minutes without moving, until a deep brown crust forms.
  3. Step 3: Flip the steak and add 2 tablespoons butter, 3 smashed garlic cloves, and 2 fresh rosemary sprigs to the pan. Tilt the pan slightly and spoon the melted butter over the steak continuously for 4 minutes until the internal temperature reaches 135°F for medium.
  4. Step 4: Remove the steak to a plate and tent with foil to rest while you make the sauce.
  5. Step 5: Pour off excess fat from the pan, then add 1/4 cup balsamic vinegar and 1/4 cup beef broth. Simmer over medium heat, scraping up browned bits, until the sauce thickens slightly, about 3-4 minutes.
  6. Step 6: Slice the steak against the grain and drizzle with the rosemary-balsamic reduction before serving.

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