Introduction

This Balsamic Flank Steak recipe combines tangy, savory flavors with tender, juicy meat and grilled zucchini. Finished with a creamy feta sauce and a rich balsamic glaze, it makes for an impressive yet simple meal perfect for any occasion.

A white plate holds a dish with three layers: the bottom layer is a spread of smooth, creamy white sauce spread unevenly; the middle layer consists of several long grilled zucchini slices with dark grill marks, light green skin, and pale yellow flesh placed diagonally; the top layer is made up of thick slices of medium-rare steak with a dark charred crust, pink inside, drizzled with a thick dark balsamic glaze and garnished with fresh green basil leaves and small sprigs of herbs scattered on top. The plate rests on a white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1.5 lb flank steak
2 teaspoons Dijon mustard
4 cloves garlic, minced
2 teaspoons onion powder
3 tablespoons soy sauce or coconut aminos
3 tablespoons olive oil
1/2 cup balsamic vinegar (plus more as needed)
Salt and black pepper to taste
3 large zucchini, ends trimmed and cut into thick slices lengthwise
2-3 tablespoons olive oil
Kosher salt to taste
8 ounces feta cheese (in the brine)
3 tablespoons heavy cream or milk

Instructions

Step 1: Combine Dijon mustard, minced garlic, onion powder, soy sauce, olive oil, and balsamic vinegar in a large plastic bag or shallow dish. Season both sides of the flank steak with salt and pepper, then add it to the marinade. Refrigerate for at least 2 hours or overnight.
Step 2: Preheat your outdoor grill to high heat (450°F) and brush the grates with oil. Remove the steak from the marinade, shaking off excess but keep the marinade for later. Place the steak on the grill, close the lid, and cook for 3-5 minutes per side for medium-rare, or until it reaches an internal temperature of 135°F.
Step 3: Brush the zucchini slices with olive oil and sprinkle with kosher salt. When you flip the steak, add the zucchini to the grill and cook for 2-3 minutes on each side until tender with charred grill marks. Press down gently with tongs to enhance grill marks.
Step 4: Transfer the steak and zucchini to a cutting board and let the steak rest for 10 minutes.
Step 5: Pour the reserved marinade into a medium saucepan and bring to a rolling boil over medium-high heat to ensure safety. Once boiling (165°F or higher), reduce heat and simmer for 2-3 minutes until thickened to a glaze consistency. Add extra balsamic vinegar if needed.
Step 6: Blend the feta cheese and heavy cream or milk until smooth using a blender or food processor.
Step 7: Brush half of the balsamic glaze over the steak, then slice thinly against the grain.
Step 8: On each plate, spread a layer of the creamy feta sauce, arrange the sliced steak and grilled zucchini on top, drizzle with the remaining balsamic glaze, and serve.

Tips & Variations

For more intense flavor, marinate the steak overnight. If you prefer a spicier kick, add a pinch of red pepper flakes to the marinade.
Use coconut aminos instead of soy sauce for a gluten-free option.
Swap zucchini for summer squash or bell peppers for variety.
Letting the steak rest ensures the juices redistribute, keeping it tender and flavorful.

Storage

Store leftover steak, zucchini, and sauces separately in airtight containers in the refrigerator for up to 3 days. Reheat gently in a skillet or microwave to prevent overcooking. The glaze and feta sauce can be warmed slightly or served at room temperature.

How to Serve

A white plate holds a layered dish starting with a base of creamy white sauce spread unevenly across the bottom. On top, there are a few long, grilled slices of zucchini with distinct dark grill marks and a light green outer peel. Resting on the zucchini are thin slices of medium-rare steak, showing a pink center with a dark, charred crust. The steak is generously drizzled with a shiny, dark brown sauce. Scattered on top of everything are small fresh green basil leaves and tiny sprigs of herbs, adding a fresh touch of color. The plate sits on a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I cook this flank steak indoors?

Yes, you can grill the steak and zucchini on a grill pan or broil them in the oven. Adjust cooking times accordingly and watch closely to prevent burning.

How do I know when the steak is cooked to medium-rare?

The internal temperature for medium-rare is about 135°F. Use a meat thermometer to check. The steak will continue to cook slightly while resting.