Season the ribeye loin generously with salt and black pepper on both sides. Heat a cast iron skillet over high heat and add olive oil. When the oil is shimmering, add the ribeye and sear for about 4-5 minutes on each side for medium-rare. Remove from skillet and let rest.

Onion Preparation

Char the Onions

In the same skillet, reduce heat to medium and add butter. Peel and slice cipollini onions and add them to the skillet. Sauté until caramelized, about 8-10 minutes. Add balsamic vinegar and cook for an additional 2 minutes. Set aside.

Mashed Potatoes Preparation

Make the Mashed Potatoes

Peel and cut russet potatoes into chunks. Boil in salted water until tender, about 15-20 minutes. Drain and return to pot. Add butter and milk, then mash until smooth. Season with salt to taste.

Steak Sauce Preparation

Prepare the Steak Sauce

In a small saucepan, combine soy sauce, Worcestershire sauce, brown sugar, minced garlic, ground mustard, and black pepper. Bring to a simmer over medium heat, stirring until the sugar dissolves. Simmer for 5 minutes and remove from heat.

Final Assembly

Plate the Dish

Slice the ribeye and serve on a plate with a generous serving of mashed potatoes, topped with charred cipollini onions. Drizzle with Vivian’s famous steak sauce before serving.