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Stuffed flank steak filled with muenster cheese, sautéed mushrooms, prosciutto, and arugula — grilled in a cast iron skillet and sliced into pinwheels. Ready in 45 minutes.
The first time I tried to make stuffed steak, it was a failure.
The cut was too thick and the inside never cooked through — by the time the center was done, the outside was overcooked and the whole thing fell apart when I tried to slice it.
Switching to flank steak fixed everything. It butterflies cleanly into a thin, even sheet, takes seasoning well, and rolls tight enough to hold everything inside.
Once you slice it into pinwheels at the table, it looks like something that took much longer than it did.
This grilled stuffed flank steak is filled with muenster cheese, sautéed mushrooms, prosciutto, and arugula — and it has been my go-to for summer cookouts ever since.
The thing that made this repeatable was the skillet.
Grilling a cheese-stuffed roll directly on the grates means melted cheese dripping into the burners and a mess.
I use a ribbed cast iron skillet set inside the grill instead — the steak gets good color and real grill heat without the cheese going everywhere.
If you have never butterflied a flank steak before, the first attempt takes some patience. By the second time, it takes about two minutes.
Why You’ll Love This Recipe
Stuffed flank steak looks like a production but the actual hands-on time is about 30 minutes — the grill does the rest.
The filling of prosciutto, cheese, and mushrooms is rich enough that you do not need much else on the plate, which makes this an easy win for summer entertaining when you want to feed a crowd without spending the whole afternoon cooking.
It slices into clean, impressive pinwheels and pairs well with a simple pasta salad or a green salad — the kind of meal that feels complete without a lot of effort.
How to Make Stuffed Flank Steak
Get a thin, even butterfly before anything else — that is what holds the whole recipe together.
Reduce the heat to medium or medium-low. Cook for another 10 to 12 minutes, flipping once, until a thermometer reads 125°F in the center. Transfer to a cutting board, tent loosely with foil, and rest for 10 to 15 minutes before slicing into ½-inch pinwheels.
Wash and pat the steak dry. Place it flat on a cutting board. Using a sharp knife, butterfly the steak by cutting horizontally through the center, keeping the blade parallel to the board and stopping about 1 inch from the far edge. Open it flat like a book. (My first attempts were uneven — one half much thicker than the other — which is why an early version never cooked through. Go slow and use the sharpest knife you have.)
Season the inside surface with 1 tablespoon of steak seasoning. Lay the muenster cheese slices in an even layer, leaving about 1 inch of exposed steak on each edge. Scatter the sautéed mushrooms over the cheese, then layer on the prosciutto, then the arugula.
Starting from the wider end, roll the steak tightly and tie with baker’s twine at 1-inch intervals. In a small bowl, whisk together the olive oil, remaining 1 tablespoon of seasoning, balsamic vinegar, and Dijon mustard. Brush the mixture all over the outside of the roll.
Place a ribbed cast iron skillet inside the grill. Close the lid and preheat to medium-high heat for at least 15 minutes. Set the roll on the hot skillet and sear for 2 minutes on each of its 4 sides — about 8 minutes total.
Oven Method
Preheat the oven to 350°F. Heat 1 tablespoon of olive oil in an oven-safe skillet over medium-high heat on the stovetop. Add the steak roll and sear for 2 minutes on each of 4 sides. Transfer the skillet to the oven and cook for 10 to 12 minutes, until a thermometer reads 125°F in the center. Rest on a cutting board tented with foil for 15 minutes before slicing.
Tips
Take your time on the butterfly. A thin, even cut is what makes this recipe work — if one side ends up much thicker than the other, the steak cooks unevenly from the inside out. Use a sharp knife and go slowly. If there are thick spots, a mallet to gently pound them down helps.
Sauté the mushrooms until dry. Raw mushrooms release a lot of water when they cook. If they go in wet, the filling gets watery and the roll can slip apart on the grill. Cook them in a dry pan over medium-high heat for 7 to 10 minutes until the liquid is gone and the edges start to color — then add to the steak.
Leave a border before rolling. Keep at least 1 inch of uncovered steak on every edge before you roll. This is the margin that keeps the cheese inside. If the filling goes all the way to the edge, it pushes out when the steak tightens on the heat.
Use the cast iron skillet on the grill. You get the grill heat, the grill marks, and the even cooking — without molten cheese running into the burners. This is the step I do not skip. If you grill directly on the grates, it still works, just keep paper towels nearby.
Rest before slicing. Ten to fifteen minutes under foil is not optional. The juices need time to settle back into the meat — cut too early and they run straight out onto the board.
Use a thermometer. Every grill is different. 125°F for medium-rare is the target, and carry-over heat during rest will bring it up a few more degrees. If you prefer medium, pull it at 130 to 135°F.
What to Serve With Stuffed Flank Steak
The pinwheels are rich on their own, so the best sides are bright and light. I usually serve this with a tri-color pasta salad — cooked pasta tossed with grilled zucchini, olives, feta, and toasted pine nuts, dressed with olive oil, white balsamic vinegar, salt, and Italian seasoning. It takes about 15 minutes to put together and can be made a couple hours ahead, which means it is sitting in the fridge ready to go while the steak is on the grill.
A simple arugula salad with lemon and olive oil works just as well — the peppery greens echo what is already inside the roll and keep the plate feeling cohesive. For something more filling alongside, grilled corn or roasted potatoes round out the meal without competing with the steak.
If you want another way to use flank steak this summer, the Marinated Beef Flank Steak is worth bookmarking — a different prep approach for the same cut, built around the marinade rather than the stuffing.
Stuffed Flank Steak
Ingredients
- 1 lb flank steak
- 2 tbsp all-purpose steak seasoning, divided
- 2 tbsp olive oil
- 1 tsp Dijon mustard
- 1 tbsp balsamic vinegar
- 6 slices muenster cheese, provolone works too
- 4 oz mushrooms, sliced and sautéed until water evaporates
- 8 –10 thin slices prosciutto
- 1 cup arugula
- Baker’s twine
Video
Instructions
- Pat steak dry. Butterfly by cutting horizontally through the center, stopping 1 inch from the edge, then opening flat.
- Season the inside with 1 tbsp steak seasoning. Layer cheese, sautéed mushrooms, prosciutto, and arugula, leaving 1 inch uncovered on each edge.
- Roll tightly from the wider end. Tie with baker’s twine at 1-inch intervals.
- Whisk together olive oil, remaining 1 tbsp seasoning, balsamic vinegar, and Dijon mustard. Brush over the entire roll.
- Place a ribbed cast iron skillet in the grill. Preheat to medium-high for 15 minutes. Sear steak 2 minutes on each of 4 sides.
- Reduce to medium heat. Cook 10 to 12 more minutes, flipping once, until a thermometer reads 125°F in the center.
- Transfer to a cutting board, tent with foil, and rest 10 to 15 minutes. Slice into ½-inch pinwheels.
Notes
- Sauté mushrooms until dry before adding — wet mushrooms make the filling watery and the roll can slip apart.
- Oven method: Sear on stovetop 2 min per side, then bake at 350°F for 10–12 minutes until 125°F internal temp.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
FAQ
How do you butterfly a flank steak for stuffing? Place the steak flat on a cutting board. Hold a sharp knife parallel to the board and cut horizontally through the center of the meat, stopping about 1 inch from the far edge. Open it flat like a book — you should have one thin, even piece roughly twice the original surface area. If any spots are noticeably thicker, give them a few gentle taps with a meat mallet to even them out. My early attempts were uneven, which is exactly why the steak in my first try never cooked through properly — take your time here.
What temperature should stuffed flank steak reach? 125°F in the center for medium-rare. Carry-over heat during the rest period will bring it up a few degrees more. For medium, pull it at 130 to 135°F. I always use a thermometer with stuffed steak because the rolling changes how heat travels through the meat — timing alone is not reliable the way it might be with a flat steak.
Can I make stuffed flank steak ahead of time? Yes — you can butterfly, fill, roll, and tie the steak up to a day in advance. Keep it wrapped tightly in the refrigerator. Brush with the oil and seasoning mixture right before grilling. The cold actually helps the roll hold its shape — it stays compact and is easier to handle on the grill than a freshly rolled room-temperature steak.
What is the best cheese for stuffed flank steak? Muenster is what I use most often — it melts evenly and has a creamy, mild flavor that does not overpower the prosciutto or mushrooms. Provolone is a reliable substitute and adds a slightly sharper note. I would avoid anything too firm like aged cheddar or too crumbly like feta — they do not bind the filling the same way and tend to fall out when you slice the pinwheels.
I’ve never made flank steak before, but I think I need to start! This looks delicious, Mira! I love that it’s stuffed with cheese and prosciutto! And that pasta salad is calling my name. What a delicious meal for the summer!
Oh! That tri color pasta is speaking to me. Love how summery and delicious this looks. Such a perfect meal combo for warm weatehr!
Goodness! This is a perfect summertime meal! Its deliciousness is jumping right off the page!
Thanks for the delicious recipe! Never realized how easy to make stuffed flank steak is.