Roast Chateaubriand with cèpes, roscoff onions and creamed potatoes
Serves 2:
1 | chateaubriand, sinew removed |
300g | cèpe mushrooms |
2 | roscoff onions |
1 | bunch chives |
Potatoes for mash (rooster/maris piper/king Edward) | |
250 ml | double cream |
1 | pack of unsalted butter |
1 | bunch of thyme |
1 | clove of garlic |
250ml | beef stock |
cherry vinegar |
The cèpe season is in full swing, and for us chefs it’s a highlight of the year. They have a unique flavour and if you’re not already, I suggest you jump on board. I always cook my mushroom ragoût with some form of onion and right now, roscoffs from Brittany are also a seasonal treat.
- First season the beef generously with salt and freshly ground black pepper. In a hot pan sear it in hot oil all over, add 50 g of the butter and when it foams toss in the garlic and a few sprigs of thyme.
- Place the beef in the oven at about 180 degrees. It shouldn’t take longer than 15 mins, but a good way to test is to pierce the meat with a thin skewer for 10 seconds and test it on the inside of your wrist. For medium rare it should be blood temperature, about 38 degrees.
- While the beef is cooking, tend to the mash. Peel and quarter the potatoes and boil them gently starting from cold water, seasoned with a pinch of salt. Careful not to cook the potatoes too quickly or for too long as they will absorb the water.
- Once cooked drain them in a colander and let the steam evaporate. Pass through a potato ricer and keep warm.
- Boil the cream and remaining butter, and add to the potatoes to the consistency you prefer.
- Clean the cèpes by scraping the stems with a sharp knife and brushing the caps with a damp j cloth. Slice them thinly.
- Peel and slice the onions, season and sweat gently in a little butter. When soft, add the cèpes to the pan.
- After 3 or 4 minutes throw in the chopped chives and a splash of sherry vinegar.
- The beef should be well rested by now so remove it from the pan, discard the excess fat and deglaze with a good splash of Madeira. Add the beef stock reduce to taste.
All you have to do now is carve and enjoy!