Seared Round Steak

Place steak between two pieces of parchment paper and pound with the spiked side of a meat mallet just until tenderized—avoid thinning out the steak. Season generously with salt and pepper. Place steak into a resealable bag or container. Pour in olive oil, vinegar, red pepper flakes, and oregano. Finely grate 1 garlic clove straight into the bag and mix to combine. Let marinate at room temperature for 30 minutes.  Remove steak from marinade and pat very dry. Peel and crush remaining 2 garlic cloves.  In a medium cast-iron skillet over medium-high heat, heat vegetable oil. Add steak and cook, flipping once, until a deep golden crust begins to form on both sides of the steak, about 5 minutes total. Reduce heat to medium low and add butter, crushed garlic, and rosemary to pan. Using a kitchen towel, carefully grip the skillet handle and tilt pan towards you so that the melting butter forms a pool at the bottom of the skillet. Using a spoon, continually baste butter onto steak to form a deeper golden crust. Flip steak and repeat, 2 to 3 minutes in total.  Using a meat thermometer, check for doneness: 120-125°  for medium rare, 130°F for medium. Transfer steak onto a cutting board and let rest 10 minutes.  Thinly slice against the grain and return to skillet to serve over the juices. Top with flaky salt.