"This gorgeous beef tenderloin recipe with winter vegetables is sure to steal the show on Christmas Day. Using the reverse sear method, the whole beef tenderloin is slow roasted in a low oven then seared on the stove top!"
1. Preheat the oven to 250º. Season all sides of your trimmed and tied beef tenderloin with salt and pepper. This can be done 24 hours in advance and stored in the fridge uncovered. Transfer beef to a large, oven safe skillet and beef in the oven. Roast until the internal temperature is 20º below the final desired temperature. (About 30 minutes to reach 105º for medium rare.)
2. Meanwhile prepare the vegetables. Peel potatoes then chop into 1/2 inch chunks. Place in a medium saucepan and add enough cold water to cover by one inch. Cover, bring to a boil, uncover and boil for 4 - 6 minutes. Potatoes will begin to soften, but still retain their shape. Drain potatoes then rough up the edges by shaking in a metal colander. Place potatoes in a medium mixing bowl, drizzle with avocado oil, then add dried tarragon, salt, and pepper. Stir to coat then spread the potatoes in a single layer on a baking sheet.
3. Peel, quarter, and slice the beets. Halve the brussels sprouts. In a medium mixing bowl combine avocado oil, apple cider vinegar, salt, and pepper. Add veggies and toss to coat. Spread the beets in a single layer on a baking sheet, retaining the Brussels sprouts in the bowl for later.
4. When the beef reaches its initial, pre-searing cooking temperature remove it from the oven, cover with foil, and keep warm. Increase the oven temperature to 400º and adjust the racks so that you have one upper and one lower rack.
5. Place the potatoes on the bottom rack and roast for 15 minutes. After 15 minutes place the beets in the oven on the top rack and set a second 15 minute timer.
6. At the end of the second 15 minute timer remove both pans from the oven. Flip the potatoes, rotate the pan, and place it back in on the top rack. Flip the beets then gather to one side of the sheet pan, adding the brussels sprouts to the now empty side. Return the beets pan to the oven on the bottom rack. Roast all together for the third and final 15 minutes.
7. In a small saucepan, melt the salted butter over a medium low heat swirling occasionally. Butter will bubble and foam up. Once the foam subsides, monitor it closely. When the milk solids brown and start to smell nutty, remove from the heat and add in the julienned sage leaves. Swirl the pan. The butter will foam up again as it fries the sage. Set aside and keep warm.
8. About 15 minutes before the vegetables are done, transfer the beef from the skillet to a carving board. Wipe out the skillet with a paper towel, then preheat it over medium high heat on the stove top. Add a couple tablespoons of avocado oil and allow to heat. Sear all sides of the beef tenderloin, then transfer back to the carving board to rest while you finish the vegetables.