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This Grilled Flank steak is simply seasoned, grilled, then topped with a sweet and savory caramelized onion sauce.
Ah, grilling season! I love you so. I especially love the chance to grill cuts like flank steak, that only taste good to me when cooked on the grill! This is our first flank steak of the season. Trust me, there are many more to come!
I love flank steak because it has intense flavor and is super affordable. We typically rub it in cumin and chile powder, grill it, and top it with fresh corn and tomato relish. YUM! But this time, I wanted to try something different. I spied this recipe in my local grocery store’s mailer, which typically has some pretty great recipes. They used rib-eye, which we have deemed a “sometimes food” due to the high price of beef right now. We decided to use flank steak instead of rib-eye.
Fair warning, this is not my normal weeknight recipe. The sauce, while very hands off, takes some time to simmer. I’d recommend planning this for a special weekend dinner!
Ready for flavorful grilled flank steak topped with a decadent sauce? Let’s do it!
First, cut the onion into long slices. Add to a skillet with olive oil and butter, and set to cook and caramelize for about 25 minutes until golden brown.
While the onions are caramelizing, start the remainder of the sauce in a small saucepan. You’ll add what feels like every condiment in your fridge (ketchup, soy sauce, lemon juice, etc.), but I promise it goes very quick and is worth it!Let the brown sauce simmer for about 25 minutes until it’s well reduced and bubbly, then add to the finished caramelized onions.
While I was in the kitchen working on the sauce, my husband got the grill fired up. He rubbed the flank steak with garlic powder and black pepper, then threw it on a super hot grill for about 5 minutes each side. This yielded a steak that was medium rare through the middle, and medium to medium well on the thinner end pieces.
Once the steak is done, pull it off the grill and let it rest for 5-10 minutes before slicing it to let the juices re-distribute. Top with the sauce, and serve!
Love this grilled flank steak recipe? I think you’ll also enjoy:
- Smoked Chicken Quarters
- Easy Flank Steak Tacos
- How to Smoke a Whole Turkey for Thanksgiving
- Easy Lobster Tacos
- Easy Turkey Scallopini
For the steak
For the sauce
For the caramelized onion sauce
For the steak
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