Lamb fillet with rosemary jus
============================= 2020-03-03

Comment: Slow cooking or regular cooking, it's up to you. I opted for slow cooking and it worked well. It is normally recommended to cook the fillet for an interior temperature of 55C, I chose 57C and the next time I will try 60C.
Do not hesitate to sear well the meat first in a little oil or a butter/EVOO mixture.
Preheat the oven with a rack, itself in a baking sheet to 80C. A good idea is to place a parchment paper in the baking tray to collect the few drops of liquid that could fall, this will avoid some dishes.
The cooking time is a little unpredictable. A small fillet (2.5 cm thick - 1") will cook in ~1 h, a larger one can take 90 to 120 minutes. However, once the internal temperature has been reached, you can lower the oven to 60C and let the meat sit there for up to 1 hour without any problem.
In case of rapid cooking, sear the meat, then place it in the oven preheated to 230C for 8 to 10 minutes for a lamb fillet.
Serve the meat in slices, preferably on preheated plates, with a small sauce, for example the rosemary juice described here.

4 people


lamb fillet ~150g pp
butter/EVOO or oil
S + P


Salt and sear the meat in a very hot pan, in a little butter/EVOO 2 minutes on each side.
Place it on the grid, in the preheated oven at 80C with the probe, or at 230C.

REmove from the oven and pepper.

In the case of rapid cooking, allow the meat to stand for 5 minutes before cutting it, serve immediately in the event of slow cooking.

Rosemary jus:


2 dl veal stock
3 dl red wine
5 sprigs of rosemary

1 dl red port
1 teaspoon of corn starch
30 g Butter
S + P

Put the first 3 ingredients in a saucepan.
Reduce to ~1 dl, remove the rosemary (it is probably necessary to pass the mixture through a colander to remove the remaining rosemary needles).
Mix the maizena in the port, and add it to the juice. Cook 1 or 2 minutes more, remove from heat and add the butter. Add pepper and salt if necessary.