Use a stainless steel or cast iron pan for the following: 

Bread: I used an Artisan Italian Loaf Bread, but this sandwich would taste amazing with Ciabatta bread as well. Slice bread, butter and toast in a hot pan. Set aside. 

Steak (Step 1): Pat dry using a paper towel, generously salt the steak on both sides and let rest on the kitchen counter for 15-30 minutes. 

Sautéed Onions: On low-medium heat add olive oil, butter, ½ red or yellow onion (sliced), 1-2 cloves of garlic (whole or minced), salt and freshly cracked black pepper. Stir well for about 10 minutes until onions are soft and have some color. Remove from the pan and set aside. Don’t clean the pan.

Steak (Step 2): Sear the steak on both sides to your liking (3-4 mins on each side for medium rare). Add butter, 1-2 cloves of garlic (whole), 2 sprigs of fresh rosemary or thyme. As you cook the steak, and using a spoon and/or sprig of rosemary/thyme, baste steak with the butter. Remove from the pan and let rest for 10 mins, while you make the sauce. 

Cream Mushroom Sauce: Using thongs and a piece of paper towel, slightly clean the pan. Add olive oil and butter, sauté ¼ cup of diced onions with 1 clove of garlic (whole or minced), salt and freshly cracked black pepper. Cook onions until they are translucent. Stir in 1 cup of sliced mushrooms and let cook for 5 minutes. Add ⅓ cup of Skinny Latina Mother of All Marinades and let reduce for 2 minutes. Add 3 tbsp of heavy cream and make sure to mix in the rendered juices of the steak. Stir well and allow to thicken. Season to taste and set aside. 

Assemble your sandwich: Bottom bread, a few spoonfuls of the creamy mushroom sauce, sliced ribeye, sautéed onions, more of the delicious creamy mushroom sauce and top bread. ENJOY! Buen Apetito!