Just found this recipe at Melangery last week when I was looking for a beef recipe. For some reason, I don't have as many beef recipes as I do chicken. This one looked good and easy and it turned out great, so it'll be in my recipe rotation from now on. I used balsamic vinegar (slightly less than 1/4 cup) in place of the red wine and served it with blindingly white rice.
Roasted Flank Steak with Mushrooms and Thyme
1 flank steak, about 1 1/2 lb. trimmed
1 t. chopped fresh thyme
1/4 c. dry red wine
3-4 garlic cloves, peeled, sliced
Salt and ground pepper
2 T. olive oil for marinade plus 1 Tbsp for a cooking pan
1 onion, peeled and cut into 6 wedges
2 T. unsalted butter
1 lb. mushrooms, sliced
Salt and freshly ground pepper, to taste
Place the steak in a large glass dish. Combine fresh thyme, garlic, salt, ground pepper, oil and red wine, pour over the meat. Cover the dish tightly with plastic wrap. Let the meat stand in the mixture for several hours in the refrigerator, turning occasionally. Remove the steak from the refrigerator 40 minutes before cooking. Bringing the meat to room temperature helps it to cook more evenly.
Preheat the oven to 400F.
Heat a heavy nonstick fry pan over medium-high heat. Add 1 Tbs. of the oil. Remove the steak from the marinade. Put the steak in the pan and sear it, turning once, for 3 to 4 minutes per side or until browned. Spread the marinade over steak and add onions; place pan in oven. Roast at 400° for 10-15 minutes or until desired degree of doneness. Transfer the steak to a carving board and let rest for 10 minutes before slicing.
In a large fry pan over medium heat, melt the butter. Add the mushrooms and cook, stirring occasionally, until lightly browned, 8 to 10 minutes. Season with salt and pepper, and stir to combine.
Cut the steak into thin slices on the diagonal, using a sharp knife. Serve with roasted onions and mushrooms.