Rolled Flank Steak (Stuffed Steak Pinwheels)

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  2.5 lbs Beef Flank Steak, Boneless
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  2 tbsp Butter
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  2 tbsp Olive oil

  Regular (not extra-virgin) olive oil for high-heat cooking. EVOO for dressings.

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  2 Yellow Onion(220g)
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  2.5 tsp 2½ teaspoons kosher salt
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  0.5 tsp ½ teaspoon freshly cracked black pepper
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  1 lbs Mushrooms, White, Sliced
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  4 oz Cheese, Provolone
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  2 tbsp Avocado oil
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  1 cup Wine, White, Dry
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  4 Garlic(12g)
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  0.8 cup Cream, Heavy Whipping
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  1 tsp Thyme, Fresh
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  Parsley, Fresh

Instructions

1. 1Combine salted butter and olive oil in a large skillet over medium-low heat. Once the butter has melted, stir in the onion and salt. Cover and cook 5 minutes, then remove lid and continue cooking, stirring often, over medium heat until the onion is golden brown, about 30 minutes. Add the sliced mushrooms and cook until the onion is deep golden brown and mushrooms are tender, about 10 more minutes. Transfer to a bowl and refrigerate until completely cooled, about 15–20 minutes.
2. 2Place the flank steak on a cutting board, cover with plastic wrap, and pound with a meat mallet to ⅛-inch thickness. Season both sides with salt and let rest 10 minutes uncovered.
3. 3Position the steak so the grain runs parallel to the cutting board edge. Slide butchers twine under the steak at 3-inch intervals (about 6 pieces total). Spread the cooled onion-mushroom mixture evenly over the steak, leaving 2 inches around the edge. Layer the provolone on top. Roll the steak tightly from bottom to top until seam-side down. Tie the twine, starting in the middle and working outward. Cut the roll in half and season the outside with the remaining salt and pepper.
4. 4Heat a large cast iron skillet over medium-high heat until smoking, about 2–3 minutes. Place the steak rolls seam-side up in the skillet and sear 3 minutes per side until deeply browned, 9 minutes total.
5. 5Preheat the oven to 350°F. Transfer the skillet to the oven and cook until the internal temperature reaches 130°F, about 10 minutes. Remove from the oven and transfer the steak rolls to a platter to rest for 10 minutes.
6. 6Return the skillet to the stovetop over medium heat. Add the garlic and cook, stirring, until fragrant, about 1 minute. Add the white wine and increase heat to medium-high. Bring to a simmer, scraping up browned bits. Add fresh thyme and cook until liquid reduces to about ¼ cup, about 4–5 minutes. Stir in the heavy cream, bring back to a simmer, and cook over medium heat, stirring often, until thickened slightly, about 2 minutes. Whisk in salted butter and season with black pepper.
7. 7Remove twine from the steak rolls and cut into 1-inch slices. Divide evenly into 6 airtight containers while hot. Top with the sauce