Flank steak is a fairly popular cut of beef, and for good reason — it's flavorful, inexpensive, and incredibly versatile! Unfortunately I've had my fair share of tough ones over the years; the lean meat almost seems to overcook if you just look at it the wrong way. Thankfully this recipe for balsamic flank steak stuffed with prosciutto and cheese has renewed my faith in the often-too-tough meat.
I first had a variation of this recipe at my in-laws house a few years ago when my father-in-law put a few stuffed flank steaks on the grill for an impromptu family gathering. The minute the tangy beef, salty prosciutto, and melted cheese hit my tongue, I knew it was a keeper. I've played around with the marinade since then, but I always come back to this creamy balsamic dressing (the longer the soaking time the better).
While grilling this steak is fantastic, a cast iron skillet in the oven is the perfect tool for rainy days and chilly weather. Cooking this type of cut, or any cut for that matter, on cast iron is my preferred method because the pan gets smoking hot, allowing the meat to form a gorgeous brown crust with less risk of overcooking. (But don't forget an instant read thermometer to check the temp, since this is one steak you don't want to go past medium-rare!)
I love this recipe for summer entertaining, especially since it only gets better when made in advance. The flank steak can be marinated a day or two ahead of time, rolled, and then refrigerated until ready to cook. Even better, the ingredients can be adjusted to whatever you have on hand. If you don't have provolone try swiss or mozzarella. No spinach? Try basil or arugula. To me, summer is all about a little flexibility, even though I have a feeling you will be enjoying this recipe year-round.
Balsamic Marinated Stuffed Flank Steak
Serves 2 to 4
For the marinade:
1/2 cup balsamic vinegar
2 tablespoons Dijon mustard
2 garlic cloves, peeled and sliced
1 cup extra-virgin olive oil
1 teaspoon kosher salt
Freshly ground black pepper
1 (2- to 3-pound) flank steak
For the stuffing:
3 ounces prosciutto
6 slices provolone cheese
1 cup spinach, basil, or arugula
Kosher salt and pepper
Neutral cooking oil, such as canola
For the marinade, combine balsamic vinegar, Dijon, and garlic in a blender and puree until smooth. With the machine running, slowly pour in the oil until thick and creamy. Season with salt and pepper.
Transfer the mixture to a plastic zip-top bag (or vacuum seal) and add the flank steak. Remove excess air and refrigerate, turning occasionally, for a minimum of 4 hours and up to 24 hours.
Remove the flank steak from the marinade and pat dry, discarding the marinade. Arrange the steak on a clean work surface so the long edge runs perpendicular to you. Using a sharp knife and cutting parallel to your work surface, butterfly the steak in half lengthwise. Make sure not to cut all the way through. (Leave a 1/2- to 1/4-inch portion along the edge.) Fold open the meat like you would a book and gently flatten the seam to form a rectangle. Using a meat mallet or rolling pin, pound the steak to a 1/4-inch thickness.
Arrange the meat on a work surface with the grain running north and south. (You want to roll the steak this way so that when it is cut, you slice it perpendicular to the grain.) Lightly season the top with salt and pepper. Lay the prosciutto slices in an even layer parallel to the grain, leaving a one-inch space at the top edge. Next add the provolone, followed by the spinach.
Start rolling the flank steak away from you (south to north), making sure to keep it as compact as possible as you roll. Once rolled, tie the stuffed roll in regular intervals with kitchen twine and season the outside with salt and pepper. (At this point the rolled flank steak can be refrigerated for up to two days.)
To cook the steak the oven: Preheat oven to 350°F. Add a few tablespoons oil to a large cast iron or oven-proof skillet and heat on medium-high to high until smoking. Add the rolled flank steak to the pan and sear until deep golden brown on all sides, 8 to 10 minutes. Transfer the skillet to the oven and continue cooking until an instant-read thermometer reads 125°F in the middle of the roll, 8 to 10 minutes. Transfer the steak to a cutting board and tent loosely with aluminum foil. Allow to rest for 10 to 15 minutes before slicing. Snip the strings and cut steak into 1/2 to 3/4-inch slices.
To cook the steak on the grill: Place a large cast iron skillet in the grill, close lid, and turn all burners on high for 12 to 15 minutes. Keep half of the burners on high heat and turn remaining burners down to low. (Make sure the skillet is over the high burners.) Add the rolled flank steak to the pan, close the grill, and sear until deep golden brown on all sides, 8 to 10 minutes. Transfer the skillet to the cooler side of the grill, cover, and adjust heat to maintain a grill temperature of 325°F to 350°F.
Cook the steak on the grill until an instant read thermometer reads 125°F in the middle of the roll, about 8 to 12 minutes. Transfer the steak to a cutting board and tent loosely with aluminum foil. Allow to rest for 10 to 15 minutes before slicing. Snip the strings and cut steak into 1/2 to 3/4-inch slices.
A cast iron is not completely necessary on the grill, but it allows for even searing and prevents cheese from dripping through the grates, which can cause flare ups.