Slow Roasted Filet of Beef With Basil Parmesan Mayonnaise

TENDERLOIN 1. Preheat oven to 275F 2. Place the meat on a sheet pan and pat it dry with paper towels. Brush it all over with the oil, reserving about 1//2 tbsp. Sprinkle the meat all over the with the salt and pepper. It will seem like a lot, but it makes a difference. Place the tarragon branches around the beef, tying them in 4 or 5 places with kitchen string to keep them in place, and then brush the tarragon with the reserved oil. 3. Roast the meat for 1 1/4 to 1 1/2 hours, until the temperature registers 125F in the center for rare and 135F for medium rare. You can place the thermometer horizontally through the end of the beef. Cover the filet with aluminum foil and allow to rest for 20 minutes. Slice thickly and serve warm or at room temperature with Basil Parmesan Mayonnaise. MAYONNAISE 1. Place the egg yolks, lemon juice, parmesan, mustard, basil, garlic, 1 tbsp. salt and 1 tsp pepper in a food processor fitted with the steel blade. Process for 20 seconds, until smooth. 2. Combine the vegetable oil and olive oil in a 2 cup liquid measure. With the processor running, slowly pour trhe oil mixture through the feed tube to make a thick emulsion. 3. Taste for seasonings - the mayonnaise is a sauce so should be highly seasoned. 4. Refrigerate until ready to use. The sauce can be kept for up to a week.