Flank Steak With Roasted Garlic Sauce

The first time I made roasted garlic sauce, my husband kept wandering into the kitchen asking what smelled so incredible. The house fills with this mellow, sweet aroma that makes everyone gravitate toward the stove.

I served this at our anniversary dinner last fall. We ended up eating at the kitchen island instead of the fancy table setup because neither of us wanted to wait another second to dive in.

Ingredients

• Flank steak: This cut has incredible beefy flavor and the perfect texture for slicing thin against the grain
• Whole garlic bulbs: Roasting tames the sharpness and draws out natural sweetness you cannot get any other way
• Heavy cream: Creates that velvety, restaurant style consistency that clings beautifully to the meat
• Dijon mustard: Just enough tang to cut through the richness and wake up all the flavors
• Fresh lemon juice: Brightens the whole sauce and keeps it from feeling too heavy
• Beef broth: Forms the savory foundation that makes this sauce taste deeply satisfying

Instructions

Roast the garlic ahead:

Slice the tops off both garlic bulbs and drizzle with olive oil. Wrap them tightly in foil and let them roast at 400°F for about 30 minutes until the cloves feel soft and buttery when pressed.

Season the steak generously:

Pat the flank steak completely dry with paper towels. Rub it all over with olive oil then sprinkle generously with kosher salt and fresh black pepper on both sides.

Sear until deeply browned:

Heat an ovenproof skillet over medium high heat until it is nearly smoking. Sear the steak for 3 to 4 minutes per side until you have a gorgeous dark crust.

Finish in the oven:

Transfer the skillet directly into the 400°F oven. Roast for 6 to 8 minutes for medium rare or adjust the time based on how you like your steak cooked.

Let it rest properly:

Move the steak to a plate and cover loosely with foil. Give it a full 10 minutes to rest so all those juices redistribute throughout the meat.

Build the creamy sauce:

Squeeze the soft roasted garlic cloves out of their skins and into a saucepan. Add the broth and simmer while whisking to break up the garlic into a smooth base.

Finish with richness:

Stir in the heavy cream, butter, Dijon mustard, and lemon juice. Let everything simmer gently for 2 to 3 minutes while whisking until the sauce thickens slightly. Taste and adjust the seasoning as needed.

Slice and serve:

Cut the flank steak thinly against the grain into short strips. Arrange the slices on plates and spoon that gorgeous roasted garlic sauce generously over the top. Sprinkle with fresh parsley if you want some color contrast.

Save Pin

This has become our go to when we want something that feels indulgent but comes together faster than you would expect. The leftovers make incredible steak sandwiches the next day.

Making Ahead

You can roast the garlic up to two days in advance and keep it in the refrigerator. The sauce comes together in minutes when the garlic is already softened and ready to squeeze out.

Temperature Guide

Use an instant read thermometer to take the guesswork out of doneness. Medium rare hits 130°F to 135°F while medium reaches 140°F. Remember the temperature will rise a few degrees as the steak rests.

Serving Suggestions

Crispy roasted potatoes soak up the sauce beautifully. A bright arugula salad with lemon vinaigrette cuts through the richness and makes the plate feel complete.

• Crusty bread is essential for sopping up any extra sauce
• A bold red wine like cabernet sauvignon stands up to the beef
• Keep the sides simple so the steak remains the star

Save Pin

There is something deeply satisfying about a dish that looks impressive but comes from such straightforward techniques. Enjoy every bite.

Recipe Questions & Answers

→ How do I know when the flank steak is done?

Use a meat thermometer to check internal temperature. Medium-rare reaches 130-135°F, medium reaches 140-145°F. Remember the steak continues cooking slightly while resting.

→ Can I prepare the roasted garlic sauce ahead of time?

Yes, roast the garlic bulbs up to 2 days in advance and store refrigerated. Complete the sauce just before serving for the best texture and flavor.

→ What's the best way to slice flank steak?

Always slice thinly against the grain—this means cutting perpendicular to the muscle fibers running through the meat. This technique ensures tender, easy-to-chew pieces.

→ Can I substitute the heavy cream in the sauce?

Half-and-half works for a lighter sauce, though it will be less thick. For dairy-free, use full-fat coconut milk, though the flavor profile will change slightly.

→ What sides pair well with this dish?

Roasted potatoes, steamed green beans, asparagus, or a crisp green salad complement the rich flavors. Mashed potatoes also work beautifully to catch extra sauce.

→ How long should I let the steak rest?

Rest for at least 10 minutes tented with foil. This allows juices to redistribute throughout the meat, ensuring each bite remains juicy and flavorful.