Preparing the Ingredients: 1. Let the steak and burrata sit at room temperature for 20-25 minutes. To Make the Caramelized Onions: 1. Add 2 tablespoons butter to a skillet over medium high heat. Once melted, add the thinly sliced onion. Cover with a lid and let cook for 8 minutes. 2. Stir the onions to keep from burning as you pour in ¼ cup water. Continue this cooking process until the onions are deeply caramelized, about 10-15 minutes. To Make the Crostini: 1. In the meantime, turn your oven on to BROIL. 2. Slice the baguette into ½” slices. Place on a parchment paper lined sheet pan and generously drizzle with olive oil. 3. Broil for 1-2 minutes, flip the bread slices, and broil another 1-2 minutes, until golden. To Cook the Steak: 1. Preheat oven to 400F. 2. Heat up a cast iron skillet over medium high heat for 2-3 minutes, until hot. 3. Season the steak generously with salt and black pepper. 4. Add 1 tablespoon olive oil into the hot skillet. 5. Add the steak into the skillet to sear for 2-3 minutes untouched, then flip. 6. Sear another 1-2 minutes, then add the butter and rosemary sprigs to cook an additional 1 minute. Baste the steak in the melted butter during that last minute of cooking. 7. Carefully transfer the skillet into the oven to finish cooking another 3-4 minutes, or until desired wellness. Remove the steak from the skillet to rest at least 5 minutes before thinly slicing. To Make the Burrata: 1. In the meantime, combine the burrata, 1 tablespoon olive oil, and zest of 1 lemon. Season with salt and black pepper to taste. To Assemble: 1. Rub the crostini with the whole garlic cloves, then layer with the burrata, a thin slice of steak, caramelized onions, and freshly chopped chives to be enjoyed!