This grilled keto flank steak with Greek marinade is easy to make, full of zesty flavor and deliciously tender and juicy.

This keto flank steak with Greek marinade is zesty, full of flavor and wonderfully tender and juicy. Greek and Mediterranean flavors shine in this steak marinade, thanks to the extra-virgin olive oil, lemon, garlic, oregano, thyme and rosemary.
This well-balanced Greek marinade can be used on almost any cut of steak and even chicken and pork. Plus, the marinade is so easy throw together, and you likely have most of the ingredients already in your pantry.
Since flank steak is a leaner, tougher cut of beef, it's essential to marinate. We recommend marinating for at least 2 to 3 hours, so the steak has time to tenderize and become infused with flavor.
Additionally, it's best to quickly sear flank steak over high heat to seal in the juices. We recommend grilling it over high heat for 3 to 5 minutes per side, which produces tender, juicy meat. Grilling is not only quick and easy to do, but it adds a delicious smoky flavor to the meat.
And this flank steak with Greek marinade pairs well most sides. Here we've paired it with tzatziki and a fresh Mediterranean cucumber and tomato salad. But, you could pair it with most salads, roasted veggies or other Mediterranean-inspired dishes.
Keto Greek Marinade for Steak
This Greek marinade for flank steak is similar to the marinade used for beef souvlaki, a popular Greek dish, since it's made with olive oil, lemon juice, garlic, and herbs like oregano and thyme. The lemon juice is an acid that tenderizes the meat, while the garlic, herbs and oil infuse flavor in the steak.
It's essential to marinate flank steak since it's a leaner, tougher cut of beef. We recommend marinating for at least 2 to 3 hours or even overnight.
About Flank Steak
Flank steak is a leaner and slightly tougher cut of beef that comes from the abdominal muscles of the cow. It's typically less expensive than more tender cuts of meat that include more marbling of fat.
Since it's a tougher cut of meat, it's essential to marinate (which helps tenderize it) and quickly sear at a high temperature (grilling recommended) to seal in the juices. Additionally, when done cooking, you'll want to let it rest for 5 minutes and then slice it against the grain for more tender slices of flank steak.
Ingredients

Just a few notes on key ingredients:
- Flank steak: Flank steak is typically carried in most meat departments of grocers. It's less expensive than other more tender cuts of beef. If your butcher doesn't have on hand, you can substitute with skirt or flap steak.
- Extra-virgin olive oil: Olive oil helps the flavors penetrate the steak and keep it moist.
- Lemon juice: Acid is a must in the marinade since it helps tenderize the meat.
- Garlic: Garlic is key ingredient that adds flavor to the marinade.
- Oregano, thyme and rosemary: These are common herbs used in Greek marinades and cooking.
- Salt and pepper: Be sure to generously season steak with salt and pepper before marinating. We use 1 teaspoon of salt per pound of meat and about ½ teaspoon of pepper.
How to Make
STEP 1: Pat steak dry with paper towels. Season both sides with salt and pepper.
STEP 2: In a large bowl or container for marinating, whisk together olive oil, lemon juice, minced garlic and herbs. Add steak and cover in marinade. Cover bowl and refrigerate for at least two to thee hours or overnight (but no longer than 12 hours).


STEP 3: Remove steak from fridge 30 minutes before grilling (to come to room temperature). Preheat grill to medium-high heat (roughly 400 degrees F or more). Place steak directly over heat and grill for 3 to 5 minutes per side (depending on thickness) until charred and medium rare (130 degrees F on a thermometer). Place on a plate and cover with tinfoil.
STEP 4: Let steak rest for 5 minutes. Slice meat against the grain (perpendicular to lines) to keep meat tender. Top with a few squeezes of lemon juice and chopped parsley (optional). Serve immediately.


Expert Tips for Marinating Steak
- Before marinating steak, pat dry with paper towels.
- Generously season the steak with salt and pepper before marinating.
- Marinate the steak for at least 2 to 3 hours or overnight (but no longer than 12 hours) in the fridge, covered. Marinate in covered bowl or sealable plastic bag.
- Take the steak out of fridge 30 minutes before grilling to let it come to room temperature. This will help it cook more evenly.
- To char the exterior, preheat the grill to medium-high heat. When done preheating, then add marinated steak.
- The steak should be cooked to medium rare. We cook until internal temperature reaches 130 degrees F on a digital food thermometer. Please note steak will continue to cook and raise several degrees in temperature after removing from grill. If you overcook, the steak will turn tough and chewy.
- When slicing be sure to cut against the grain, perpendicular to the lines in the steak. If you cut with the grain, the steak may end up chewy.
- If you don’t have a grill, you can cook on the stovetop in a heavy or cast iron skillet over high heat until seared on each side and internal temperature reaches 130 degrees F.
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Recipe

Grilled Keto Flank Steak with Greek Marinade
Ingredients
- 1 pound flank steak
- 1 teaspoon salt and pepper to season
- 2 tablespoons lemon juice, freshly squeezed
- 3 tablespoons extra-virgin olive oil
- 3 cloves garlic, minced
- ½ tablespoon dried oregano
- ½ tablespoon dried thyme
- 1 teaspoon dried rosemary
Instructions
- Prepare the steak: Pat steak dry with paper towels. Season both sides with salt and pepper.
- Marinate: In a large bowl or container for marinating, whisk together olive oil, lemon juice, minced garlic and herbs. Add steak and cover in marinade. Cover bowl and refrigerate for at least two to thee hours or overnight (but no longer than 12 hours).
- Grill: Remove steak from fridge 30 minutes before grilling (to come to room temperature). Preheat grill to medium-high heat (roughly 400 degrees F or more). Place steak directly over heat and grill for 3 to 5 minutes per side (depending on thickness) until charred and medium rare (130 degrees F on a thermometer). Place on a plate and cover with tinfoil.
- Finish and serve: Let steak rest for 5 minutes. Slice meat against the grain (perpendicular to lines) to keep meat tender. Top with a few squeezes of lemon juice and chopped parsley (optional). Serve immediately.
Notes
- Before marinating steak, pat dry with paper towels.
- Generously season the steak with salt and pepper before marinating.
- Marinate the steak for at least 2 to 3 hours or overnight (but no longer than 12 hours) in the fridge, covered. Marinate in covered bowl or sealable plastic bag.
- Take the steak out of fridge 30 minutes before grilling to let it come to room temperature. This will help it cook more evenly.
- To char the exterior, preheat the grill to medium-high heat. When done preheating, then add marinated steak.
- The steak should be cooked to medium rare. We cook until internal temperature reaches 130 degrees F on a digital food thermometer. Please note steak will continue to cook and raise several degrees in temperature after removing from grill. If you overcook, the steak will turn tough and chewy.
- When slicing be sure to cut against the grain, perpendicular to the lines in the steak. If you cut with the grain, the steak may end up chewy.
- If you don’t have a grill, you can cook on the stovetop in a heavy or cast iron skillet over high heat until seared on each side and internal temperature reaches 130 degrees F.
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