- 1 beef tenderloin, trimmed and sliced or pounded flat*
- 1 small sweet onion – chopped
- 1/2 cup chopped Kalamative olives – chopped
- 1/2 bag baby spinach
- 2 tablespoons butter
- 1 cup mushrooms – chopped
- olive oil
- salt and pepper
- cooking twine for wrapping up the tenderloin
- Flaten the tenderloin*. If you’re feeling adventurous you can do this yourself (see notes below) or ask the butcher where you purchased the tenderloin and he/she will most likely do this step for you free of charge.
- In a deep skillet melt 1 tablespoon of butter and saute the diced onion, season with salt and pepper and cook until slightly tender. Then add in the chopped mushrooms and cook until tender. Lower heat and add in the olives and spinach. Stir until the spinach has wilted and reduced. Remove from pan and allow it to cool to room temp. Note – do not fill the tenderloin with hot filling, it could start to cook from the inside out.
- Lay the flattened tenderloin out and sprinkle with salt and pepper. Once the filling has cooled place a layer of filling over the entire tenderloin.
- Starting at the short end, and using both hands, tightly roll the meat into itself. Then, using cooking twine tie the roll so it stays together while cooking.
- Bake at 270F for about 1 hour or the internal temp reaches 125F, for medium-rare. Cover with foil and allow to rest at least 10 minutes prior to slicing.
- Serve with horseradish sauce or make a little gravy out of the pan drippings.
*To flatten the tenderloin – make a slit on the top of the meat but do not go all the way thru. Open the two sides like a book and press down. Place beef between 2 sheets of plastic wrap. Pound to an even 1/2-inch thickness using a meat mallet or small heavy skillet. Be careful not to pound too aggressively (as I did) because you will make holes in the beef.
You can watch the highlight reel of the process on my Instagram account.
Keywords: Beef Tenderloin, Thanksgiving, Christmas, holiday, dinner