This beef course comes at the peak of the menu, and is all about umami. Super high-quality ribeye dry-aged for 6 weeks is the beefiest beef you've ever tasted, and paired with a sauce that is the essence of mushrooms it's unlike any other. The dish is served very simply in this case with baby broccoli dressed liberally with vinegar and kumquat for some much-needed acidic contrast. I've heard some chefs say that not every dish needs a poetic or intellectual backstory, and some things should just be about pure unrestrained deliciousness; I hope this can be one of those dishes.
You may find the quantities for the beef stock recipe maddeningly under-specified. Stock is very forgiving and I typically eyeball all quantities. Even if you don't follow this particular recipe I strongly recommend using homemade beef stock for the sauce as storebought beef stock has inferior flavor and gelatin content which is key to the glossy richness we're seeking.
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For 4 servings (you will have extra beef but 2 steaks are necessary to yield 4 perfect portions)
2 ribeye steaks, dry aged 6 weeks (~900g)
For the baby broccoli:
~150g baby broccoli
For the pressure-cooked beef stock:
2 oxtail segments
~1/4lb ground beef
2 onions, diced
3 carrots, diced
1 leek, thinly sliced
~3 cloves garlic, peeled and crushed
For the mushroom jus:
300g cremini mushrooms, sliced
15g garlic, sliced
75g shallot, sliced
450g beef stock, from above
20g black vinegar (Chinkiang vinegar)
Maldon or smoked salt
Champagne vinegar in small spray bottle
Kumquats, seeded and very thinly sliced
Prepare the pressure-cooked beef stock (up to 1mo in advance): Drizzle the oxtail segments with oil and roast for 40m at 400F. Brown the ground beef in a pressure cooker. Add all remaining ingredients and barely cover with water; do not season with salt. Bring to a boil, seal and cook on high pressure for 2hrs. Depressurize with cold water. Strain. Vacuum pack and freeze if not using immediately.
Prepare the mushroom jus (up to 1d in advance): Saute the mushrooms in a pressure cooker over medium heat with butter and salt until browning, about 7-10m. Add garlic, shallot, and thyme and saute for 2m. Add the beef stock. Season. Bring to a boil, then seal and cook on high pressure for 1h. Depressurize with cold water. Strain. Reduce by half. Weigh and set at 100%; blend in 0.2% xanthan gum. Stir in the black vinegar. Adjust seasoning. Vacuum pack and chill until needed.
Prep the baby broccoli: Vacuum pack the broccoli with butter and a pinch of salt. Chill until needed.
To serve: Generously season the beef with salt and vacuum pack. Cook sous vide 1-1.5hr at 130F. Heat the mushroom jus to serve and keep warm. Steam the broccoli in the bag for 4m; drain onto a tray. Char with a blowtorch and season with the champagne vinegar. Drain the beef on paper towels. Sear in a very hot pan until browned. Cut into portions keeping some fat on the ends and reserve on paper towels. Add a portion of beef to the plate. Top with some of the Maldon or smoked salt. Arrange the baby broccoli to one side and add a few slices of kumquat on top. Spoon the mushroom jus on the other side.