-
1
Remove the trimmed and trussed tenderloin from the fridge and let it come to room temperature. This will take about an hour.
-
2
Place a 4 quart heavy bottomed pot onto the stove. Place the tenderloin into the pot and add enough stock to cover it by an inch. You may or may not use all the stock. Remove the beef tenderloin from the stock and place it onto a plate. Pate the tenderloin dry and season it with salt.
-
3
Add the garlic, fennel, Sechuan and black peppercorns to the vegetable stock. Season the stock with a teaspoon kosher salt and a few grinds fresh ground black pepper. Bring the stock to a boil then turn off the heat. Now trim all your vegetables and prep everything else while you let the stock steep with the spices.
-
4
Combine the mustard, mayo, parsley and lemon juice. Mix it well. Add some salt and pepper. Set aside.
-
5
Add the trussed tenderloin to the pot.
-
6
If you have big chunks of vegetables and some smaller ones you will want to add the veggies in stages. If the carrots are the largest add them first and so on. If they are all about the same size just add them all.
-
7
Turn the heat to medium high and bring the pot to a boil then immediately reduce the heat to a simmer. Set a timer for 10 minutes. At the end of 10 minutes turn the tenderloin if it is floating and check for doneness. Set the timer again for 10 minutes.
-
8
The tenderloin will start to look split at the edges and if you look into the cracks and see bright red you need to cook it longer. The usual way of checking the beef by squeezing works ok but the tenderloin is much squishier since it is being poached and therefore harder to gauge.
-
9
I found 30 minutes was a perfect medium rare for the tenderloin I cooked but that time may vary a little depending on size. So be careful with your cooking time and don't be afraid to remove the beef to a plate, cover it and let it rest while everything else is finishing up.
-
10
Remove the beef from the pot, let it rest covered then slice it into 1/2 inch medallions. Do not ladle hot stock over the top of the beef but instead ladle it on to the plate first. If you ladle it over the top it will cook the beef and it won't look as appealing. Place the medallions onto a platter surrounded by vegetables and and stock. Serve with Maldon salt and the mayonnaise on the side.
