This 5 ingredient London Broil steak marinade transforms budget beef into tender, juicy grilled steak.
London Broil has a reputation for being tough, but that changes completely when you give it time in a marinade that actually works. This one blends fresh garlic and onion with soy sauce, balsamic vinegar, and olive oil into a smooth, bold bath that penetrates deep into the meat. The result is steak that slices cleanly, tastes savory and slightly sweet, and stays juicy from edge to center.
The trick is patience. Six hours minimum, overnight if you can swing it. The marinade needs that time to break down the muscle fibers and infuse flavor into every layer. When you finally pull the steak off the grill at 130°F for medium-rare, slice it against the grain, and watch how cleanly the knife glides through, you’ll understand why the wait matters.
What You’ll Need for This 5 Ingredient London Broil Marinade
This marinade keeps things refreshingly simple while delivering bold, layered flavor that makes inexpensive cuts taste like something special.
- Top round or flank steak – the classic London Broil cuts that benefit most from a long marinade, turning lean and affordable beef into something tender and flavorful.
- Soy sauce – provides deep umami saltiness and helps tenderize the meat; Kikkoman offers the most balanced salt level without overwhelming the other flavors.
- Balsamic vinegar – adds subtle sweetness and acidity that brightens the marinade and helps break down tough muscle fibers.
- Olive oil – creates richness, helps the marinade cling to the meat, and contributes to better browning on the grill.
- Onion – blended into the marinade for natural sweetness and aromatic depth that mellows as it sits.
- Garlic cloves – fresh whole cloves deliver a sharper, more vibrant punch than pre-minced garlic, making the marinade taste noticeably brighter.
- Black pepper – rounds out the marinade with gentle heat and aromatic complexity.
London Broil Marinade Tips for Maximum Flavor
- Pat the steak completely dry before it hits the grill. Excess marinade creates steam instead of sear, and you need that caramelized crust to lock in flavor and texture.
- Let the meat sit at room temperature for a full hour before grilling. Cold steak cooks unevenly, leaving you with a gray band around a barely warm center.
- Flip the steak every minute during grilling to build an even crust without burning the outside while the inside stays pink.
- Rest the steak for 10 minutes after grilling, tented loosely with foil. Skipping this step means all those juices run onto the cutting board instead of staying in the meat.
How to Marinate and Grill London Broil (Step by Step)
STEP 1: Combine soy sauce, water, balsamic vinegar, and olive oil in a blender. Add the quartered onion and peeled garlic cloves, then blend until the mixture is completely smooth with no visible chunks. Season with black pepper and pulse briefly to incorporate.
STEP 2: Place the beef in a large resealable bag or shallow dish. Pour the blended marinade over the meat, making sure every surface is coated. Seal the bag or cover the dish tightly, then refrigerate for at least 6 hours or overnight for deeper flavor penetration.
STEP 3: Remove the marinated steak from the refrigerator 1 hour before grilling. Let it sit on the counter to come to room temperature, which ensures more even cooking. Pat the meat dry with paper towels to remove excess marinade and prepare it for a proper sear.
STEP 4: Heat your grill to 450-500°F until it’s smoking hot. Place the dried steak directly on the grates and cook for 8 to 12 minutes total, flipping every minute to develop an even crust while keeping the interior rare to medium-rare. Use an instant-read thermometer to check for 130°F internal temperature.
STEP 5: Transfer the cooked steak to a cutting board and tent loosely with foil. Let it rest for 10 minutes to allow the juices to redistribute. Slice the meat against the grain into 1/2-inch thick slices for maximum tenderness, then serve immediately.
What Goes Well with London Broil Steak
London Broil has enough savory richness to stand up to bold sides without getting lost.
- Roasted or grilled vegetables like asparagus, zucchini, or bell peppers pick up the same char and smokiness as the steak.
- Creamy mashed potatoes or a simple baked potato balance the meat’s intensity with starchy comfort.
- A crisp green salad with a tangy vinaigrette cuts through the richness and keeps the meal from feeling too heavy.
London Broil Marinade: Your Top Questions Answered
What cuts of beef work best with this marinade?
Top round and flank steak are the classic choices for London Broil because they’re lean, affordable, and respond well to marinating. Sirloin tip also works if you can find it at a good price, though it’s slightly more tender to begin with.
Can I marinate the steak for less than 6 hours?
You can, but the flavor won’t penetrate as deeply and the meat won’t tenderize as much. If you’re truly short on time, aim for at least 4 hours, but overnight marinating delivers noticeably better results in both texture and taste.
Is it possible to cook London Broil without a grill?
Absolutely. Use a cast-iron skillet or grill pan over high heat, or broil the steak in your oven on the top rack. Either method works as long as you get the surface hot enough to create a good sear and caramelization.
Does the marinade work for other types of meat?
It does. Chicken thighs, pork chops, and even lamb chops all take well to this marinade, though you may want to adjust marinating time based on the thickness and tenderness of the cut you’re using.
How do I know when my London Broil is perfectly cooked?
Use an instant-read thermometer and pull the steak at 130°F for medium-rare, which is ideal for this cut. Anything past 135°F starts to turn tough and dry, so err on the side of undercooking rather than overdoing it.
How to Store and Reheat Leftover London Broil
Store leftover sliced steak in an airtight container in the fridge for up to 3 days. The meat stays tender if you slice it before storing, and it’s easier to reheat in smaller portions.
To reheat, warm the slices gently in a skillet over medium-low heat with a splash of beef broth or water to keep them from drying out. You can also reheat in the microwave at 50 percent power in 30-second intervals, though the skillet method preserves more texture.
For longer storage, freeze the cooked, sliced steak in a freezer-safe bag with as much air pressed out as possible. It keeps for up to 3 months and thaws overnight in the fridge. Reheat from thawed using the same skillet method for the best results.
5 Ingredient London Broil Steak Marinade
Ingredients
Equipment
Method
- Add the soy sauce, water, balsamic vinegar, and olive oil to a blender. Drop in the quartered onion and peeled garlic cloves, then blend until the mixture is completely smooth with no chunks remaining. Add the black pepper and pulse briefly to incorporate it evenly.
- Place the beef in a large resealable bag or shallow dish. Pour the blended marinade over the meat, making sure all sides are fully coated. Seal the bag or cover the dish tightly, then refrigerate for at least 6 hours — overnight is ideal for maximum flavor and tenderness.
- Take the marinated beef out of the refrigerator 1 hour before grilling to allow it to come to room temperature, which promotes even cooking. Pat the surface thoroughly dry with paper towels to remove excess marinade — this step is essential for developing a proper sear and caramelized crust on the grill.
- Preheat your grill to 450–500°F until it is smoking hot. Lay the dried steak directly on the grates and grill for 8 to 12 minutes total, flipping every minute to build an even crust while keeping the center rare to medium-rare. Check doneness with an instant-read thermometer, pulling the steak at 130°F internal temperature for medium-rare.
- Move the steak to a cutting board and tent it loosely with foil. Allow it to rest for 10 minutes so the juices redistribute throughout the meat. Slice against the grain into 1/2-inch thick pieces for maximum tenderness and serve immediately.
