1½ pounds bavette steak, cut into 4 pieces
1 pound Cipolline onions
3 teaspoons olive oil plus more for drizzling
3 tablespoons unsalted butter
1 large head radicchio
2 teaspoons aged sherry vinegar
Salt & pepper
Preheat oven to 350°F. Let steaks sit at room temperature for at least ½ hour.
Toss onions in a baking dish with one tablespoon of olive oil and season with salt. Roast in the oven, turning over once, until dark and caramelized, about 25 to 30 minutes.
Heat a large cast iron pan on medium-high heat. Coat with 2 teaspoons of oil and then season with salt. Cook steaks for 4-5 minutes per side, or until nicely caramelized, about 125°F for medium rare. Add butter to cast iron pan. Spoon the melted butter over the steaks to baste. Let the steaks rest for about 5 minutes.
While resting, prepare the radicchio by tossing in a bowl with the vinegar and 1 teaspoon olive oil. Season with salt and pepper.
Slice steaks across the grain on a cutting board. Plate onto 4 plates and serve with Cippoline onions and radicchio salad.