Name: Irresistibly Juicy Savory Marinated Flank Steak Sandwich Recipe
Prep time: 20 min
Cook time: 15 min
Total time: 275 min
Ingredients: 1/4 cup Canola Oil (can substitute with vegetable oil); 1/4 cup Lemon Juice (freshly squeezed preferred); 1/4 cup Soy Sauce (can use low-sodium); 1 tablespoon Worcestershire Sauce (no substitute suggested); 2 tablespoons Dijon Mustard; 2 tablespoons Dark Brown Sugar (light brown sugar can be used alternatively); 1/2 teaspoon Finely Ground Black Pepper (freshly ground for best flavor); 1 teaspoon Kosher Salt (sea salt can be substituted); 4 cloves Garlic (minced) (fresh garlic is key); 1 pound Flank Steak (can use skirt steak or sirloin); 2 tablespoons Unsalted Butter (use salted if preferred); 1 tablespoon Chives (minced) (fresh herbs elevate flavor); 1 teaspoon Thyme (minced) (fresh herbs elevate flavor); 1 tablespoon Parsley (minced) (fresh herbs elevate flavor); 1 large Onion (sliced) (sweet onions preferred); 1 loaf Ciabatta Loaf (can substitute with any crusty bread); 4 slices Provolone Cheese (can swap for cheddar or pepper jack); 2 cups Arugula (spinach could serve as a substitution)

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There’s nothing quite like the joy of biting into a perfectly crafted sandwich, and my Savory Marinated Flank Steak Sandwich with Charred Onions is about to become your new favorite! Picture this: tender, juicy flank steak that has marinated for hours in a vibrant blend of spices, grilled to perfection and nestled alongside sweet, charred onions. All of this is tucked warmly in a crusty ciabatta roll, ready to deliver a symphony of flavors with every bite.

As the summer sun casts its warm glow, there’s no better way to gather friends and family than with these mouthwatering sandwiches at your next barbecue. This recipe captures the essence of casual dining—a little bit gourmet, but effortlessly achievable. Whether you’re a seasoned chef or just looking to impress, the combination of rich flavors, fresh ingredients, and an inviting aroma makes this sandwich a delightful centerpiece for your outdoor meals. Join me as we dive into the details of this culinary masterpiece and make your next gathering unforgettable!

Why Love the Savory Marinated Flank Steak Sandwich?

Irresistible flavor: The savory marinated flank steak infuses your taste buds with layers of garlic, herbs, and umami savoriness.
Ultimate tenderness: Thanks to the marinade, each bite of steak is melt-in-your-mouth tender and juicy.
Sweet contrast: Sweet, charred onions beautifully balance the rich steak, making each sandwich unforgettable.
Easy grilling: Perfect for summer barbecues, it allows you to grill the steak and onions, bringing a smoky flavor while you enjoy the outdoors.
Versatile serving: Pair with an arugula salad or sweet potato fries for a complete meal, just like with my Savory Hot Turkey for an easy crowd-pleaser.
Visual appeal: With vibrant colors and textures, this sandwich is as pleasing to the eyes as it is to the palate!

Savory Marinated Flank Steak Sandwich Ingredients

For the Marinade
• Canola Oil – Neutral oil used in the marinade; substitute with vegetable oil if desired.
• Lemon Juice – Provides brightness and acidity; freshly squeezed is preferred.
• Soy Sauce – Adds umami depth; can use low-sodium soy sauce for less salty flavor.
• Worcestershire Sauce – A tangy element for complexity in flavor; none suggested as a substitute.
• Dijon Mustard – Mild spiciness that enhances the marinade’s flavor.
• Dark Brown Sugar – Contributes sweetness and caramelizes on grilling; light brown sugar can be used alternatively.
• Finely Ground Black Pepper – Adds a kick to the marinade; use freshly ground for best flavor.
• Kosher Salt – Essential for seasoning; sea salt can be substituted if necessary.
• Garlic (minced) – Infuses the marinade with aromatic depth; fresh garlic is key for flavor.
For the Sandwich
• Flank Steak – The primary protein; skirt steak or sirloin can be used as alternatives.
• Unsalted Butter – Adds richness to the garlic-herb butter; use salted butter if preferred.
• Chives, Thyme, Parsley (minced) – Fresh herbs elevate the garlic-herb butter; use dried herbs if fresh is unavailable.
• Onion (sliced) – Sweet onions are grilled for added flavor; red onions could be an alternative.
• Ciabatta Loaf – Ideal bread for the sandwich; can substitute with any crusty bread.
• Provolone Cheese (sliced) – Creamy, melty addition; cheddar or pepper jack can be swapped for bold flavors.
• Arugula – Adds peppery freshness; spinach could serve as a substitution.

How to Make Savory Marinated Flank Steak Sandwich

Prepare the Marinade: In a bowl, whisk together canola oil, lemon juice, soy sauce, Worcestershire sauce, Dijon mustard, brown sugar, black pepper, salt, and minced garlic until smooth and fully combined.
Marinate the Steak: Place the flank steak in a resealable bag, pour the marinade over, seal it tight, and refrigerate for 4 to 8 hours to let the flavors penetrate the meat.
Make Garlic-Herb Butter: In a small bowl, mix together softened butter, minced garlic, chives, thyme, parsley, and salt until well combined. This will enhance the flavor profile of your sandwich.
Preheat the Grill: Ignite all burners and preheat your grill for about 5 minutes. Don’t forget to clean and oil the grate to prevent sticking!
Grill Onions and Steak: Brush the onions lightly with oil and add them to the grill alongside the flank steak. Cook both for approximately 5 minutes per side until they are charred and tender.
Slice Steak: After grilling, let the steak rest for 5 minutes before slicing against the grain. This ensures each piece remains tender and juicy.
Toast the Ciabatta: Spread garlic-herb butter on the cut sides of the ciabatta and grill them until golden brown, about 1 to 2 minutes. This adds an extra layer of flavor and texture!
Assemble Sandwiches: Layer the sliced steak on the grilled ciabatta, add grilled onions and cheese, cover it, and let the cheese melt from the residual heat.
Finish and Serve: Top with arugula, close the sandwich, and serve immediately for a deliciously warm and inviting meal.

Optional: Try adding pickled jalapeños for a spicy kick!

Exact quantities are listed in the recipe card below.

Savory Marinated Flank Steak Sandwich Variations

Feel free to make this recipe your own with a few simple tweaks that bring exciting new flavors and textures to your meal.

Dairy-Free: Replace provolone cheese with a dairy-free cheese alternative or skip the cheese for a lighter sandwich.
Spicy Kick: Add sliced jalapeños or crushed red pepper flakes to the marinade for a delightful heat that complements the savory steak.
Herb Medley: Swap out the chives and parsley for fresh rosemary or oregano in the garlic-herb butter for a refreshing twist. Each herb brings its own aromatic charm!
Vegetable Boost: Layer roasted bell peppers or grilled zucchini in the sandwich for added nutrition and a burst of color that enhances each bite.
Crunch Factor: Add a handful of crispy fried onions or a sprinkle of coleslaw for a delightful crunch that contrasts beautifully with the tender steak.
Different Bread: Experiment with different types of bread like a baguette or sourdough to give your sandwich a unique spin. Each bread offers its own distinct flavor and texture!
Sweet Touch: For a hint of sweetness, add a smear of caramelized onion or a drizzle of balsamic reduction inside the sandwich for a gourmet flair.

Feel encouraged to combine these ideas to create a sandwich that speaks to your taste buds while still embracing the heart of this delicious recipe!

Make Ahead Options

These Savory Marinated Flank Steak Sandwiches are perfect for busy weeknights and stress-free meal prep! You can marinate the flank steak up to 24 hours in advance to deepen those flavors beautifully. Simply whisk together the marinade ingredients, pour them over the steak, seal it in a resealable bag, and refrigerate. Additionally, you can prepare the garlic-herb butter ahead and store it in the fridge for up to 3 days. When you’re ready to serve, just grill the marinated steak and onions as directed, toast your ciabatta, and assemble the sandwiches for a delicious meal that tastes just as fresh as if it were made on the spot!

Expert Tips

• Marination Timing: Marinate the flank steak for at least 4 hours, but no longer than 8 hours to avoid mushiness.

• Preheat Properly: Ensure your grill is sufficiently preheated and well-oiled to avoid sticking and achieve those delightful grill marks.

• Slice with Care: Always slice the steak against the grain for maximum tenderness in your Savory Marinated Flank Steak Sandwich with Charred Onions.

• Tweak the Butter: Adjust the seasoning in your garlic-herb butter based on your personal taste to enhance the overall flavor of the sandwich.

• Monitor Cooking Time: Keep a close eye on the grilling time; both steak and onions should be charred yet tender to create that perfect balance of flavors.

How to Store and Freeze Savory Marinated Flank Steak Sandwich

Fridge: Store leftover sandwiches in an airtight container for up to 3 days to maintain freshness. It’s best to keep sauces separate until ready to eat.

Freezer: If freezing, wrap each sandwich tightly in plastic wrap and then aluminum foil, preventing freezer burn. They can be frozen for up to 2 months.

Reheating: For the best results, reheat the sandwiches in a skillet over medium heat. Cover with a lid to melt the cheese and warm the steak gently, about 5-7 minutes.

Assembly Tips: If making ahead, consider storing the ingredients separately to retain the freshness of the ciabatta and toppings until it’s time to enjoy your Savory Marinated Flank Steak Sandwich!

What to Serve with Savory Marinated Flank Steak Sandwich?

Create a delightful dining experience by pairing refreshing, vibrant sides and drinks with this meal masterpiece.

Arugula Salad: Crisp and peppery, arugula salad brings a refreshing contrast that balances the richness of the sandwich. Toss in some cherry tomatoes and a light vinaigrette for extra zest.
Sweet Potato Fries: These crispy, sweet treats are a crowd favorite, enhancing the savory flavors of the steak with their natural sweetness. They add a delightful crunch that everyone will love.
Grilled Vegetables: Roasted bell peppers, zucchini, and mushrooms create a colorful side that offers a smoky flavor, beautifully complementing the grilled steak and onions.
Coleslaw: A tangy coleslaw delivers a crunchy, creamy element that contrasts the savory sandwich, making every bite even more exciting. The crunchiness pairs wonderfully with the tenderness of the steak.
Corn on the Cob: Freshly grilled corn, brushed with butter and a sprinkle of lime, adds a sweet, juicy flavor that’s perfect for summer picnics and barbecues. The flavors meld perfectly with the savory sandwich.
Red Wine: A glass of robust red wine, like a Cabernet Sauvignon, cuts through the richness of the steak while enhancing its flavors. It’s a classic choice that elevates your meal to a gourmet experience.
Chocolate Brownies: For dessert, serve fudgy chocolate brownies to indulge in a sweet, decadent treat after your savory meal. The richness of the chocolate pairs beautifully with the hearty flavors from the sandwich.

Savory Marinated Flank Steak Sandwich with Charred Onions Recipe FAQs

What type of flank steak should I choose for the best flavor?
Absolutely! Look for flank steak that has a bright red color and minimal visible fat. Marbling in the meat helps enhance the flavor and tenderness. If you prefer, skirt steak or sirloin are excellent alternatives that can also yield great results.

How should I store leftovers from the Savory Marinated Flank Steak Sandwich?
Very simply! Store leftover sandwiches in an airtight container in the fridge for up to 3 days. To keep them fresh, it’s a good idea to store any sauces or condiments separately until you’re ready to enjoy them again.

Can I freeze the assembled sandwiches for later? How do I go about it?
Of course! To freeze, wrap each sandwich tightly in plastic wrap to prevent freezer burn, then wrap them again in aluminum foil for extra protection. They can be safely stored in the freezer for up to 2 months. When you’re ready to eat, let them thaw in the refrigerator overnight before reheating.

What should I do if my flank steak turns out tough?
If your flank steak is not as tender as you hoped, make sure to slice against the grain—it can make a significant difference! Additionally, marinating for the recommended time (4 to 8 hours) is crucial. No more than that, as over-marinating can lead to mushiness.

Is this sandwich suitable for those with dietary restrictions?
Great question! For allergy considerations, be aware of the soy sauce; use a gluten-free version if needed. For those with dairy restrictions, you can substitute provolone cheese with a dairy-free alternative. Plus, always check labels for specific dietary needs when it comes to sauces and condiments.

What’s the best way to reheat leftovers while keeping the sandwich delicious?
For the best reheating results, place the sandwich in a skillet over medium heat, covering it with a lid. This will help melt the cheese and warm the steak gently without drying it out, which typically takes about 5 to 7 minutes. Enjoy the deliciousness!