Directions

• Marinate. Brush the fillet with a mixture of 1 teaspoon balsamic vinegar and the Dijon mustard and leave to marinate at room temperature for 30 minutes.
• Prep. Finely chop the needles from the rosemary sprig. Preheat the oven to 80 °C and warm a large baking dish and your serving plates inside.
• Sear. Season the marinated fillet with salt. Heat a splash of olive oil in a frying pan (untreated cast iron or stainless steel is best, to develop the fond for the sauce) over medium-high heat. Sear the meat for a total of 4 minutes, turning frequently until browned on all sides.
• Glaze. Wipe any excess oil from the pan with kitchen paper. Return the fillet to the pan and deglaze with 100 ml of the red wine and 50 ml of balsamic vinegar. Add the chopped rosemary and orange zest. Simmer gently for 10 minutes, turning the fillet often so it becomes beautifully glazed in the dark liquid. If the pan runs dry, add a tablespoon of water.
• Rest and finish. Transfer the fillet to the warmed baking dish, cover loosely with foil, and let it finish in the oven at 80 °C for 15 minutes, until the core temperature reaches 58–60 °C for a rosy, juicy medium-rare.
• The sauce. While the meat rests, pour the remaining 50 ml of red wine into the frying pan to loosen the juices. Strain through a fine sieve into a small saucepan, add the veal stock, and bring to a boil. Reduce over high heat until the sauce is thick and glossy.
• Serve. Slice the fillet into medallions, arrange on the warmed plates, season with freshly ground black pepper, and spoon the balsamic reduction generously over the top.