For the beef: Roll the fillet in salt and pepper. Massage meat with olive oil. Grill to desired degree of doneness.
For the mushroom sauce: In a skillet with oil, saute mushrooms until tender. Add garlic and allow to brown lightly. Deglaze skillet with cabernet and reduce by 3/4. Add veal stock and reduce by half. Add thyme and finish with butter. Season with salt and pepper. Keep warm until ready to serve.
For the potatoes: Place potatoes in a stockpot with lukewarm water to cover, and bring to a boil. Reduce to a simmer and skim the foam off the top. Cook until tender.
In a saucepot, heat cream and butter while potatoes are cooking. Drain water from potatoes and put through a sieve, add butter and cream, and season with salt and pepper. Whip vigorously. Serve fillets with mushroom sauce and whipped potatoes.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.