Umami-crusted Beef Fillet with Porcini Butter Sauce

Umami-crusted Beef Fillet with Porcini Butter Sauce

Mushrooms, Black Pepper and Beef have long been in an inspired friendship of love. Here, they're joined in a particularly sophisticated way.  Our Umami Steak Powder adds a subtle "woodsiness" to the beef fillet, while the porcini-infused butter enriches the sauce with its tremendous umami  "truffle-like" flavor, At an affordable price - a fraction of the cost of fresh black truffles - you can be a masterchef in your own kitchen!

(Recipe borrowed and modified from Epicurious, with thanks)

Makes 10 to 12 servings
Preparation Time: 40 minutes
Total Time: 1 1/2 hours

You will need kitchen string, a large heavy roasting pan and an instant-read thermometer.


  • 1 whole beef fillet (2.8 – 3kg), trimmed of fat, silver skin and the chain (see Cooks' Notes)
  • Rough cracked salt and freshly ground black pepper
  • 200mls olive oil, divided
  • ½ cup button mushrooms finely chopped
  • 500g of sliced porcini mushrooms (or big brown mushrooms if you can find)
  • 1 cup breadcrumbs
  • 2 tablespoons of The Great Cape’s Umami Steak Powder
  • 1 tablespoon of The Great Cape’s Pure Porcini Mushroom Powder
  • ½ cup porcini-infused butter, softened (made ahead with The Great Cape’s Pure Porcini Mushroom Powder; see Cooks Notes)
  • ¼ cup all-purpose flour
  • 3 cups beef stock or a beef broth, divided
  • ½ cup chopped spring onions


  1. Heat the oven to 180°C with the rack in middle of the oven.
  2. Make a deep cut into the top side of beef fillet, about 5-6 centimetres from tail end, to facilitate folding the tail end under the roast to give the meat a more uniform thickness. Tie the fillet at 3cm intervals with kitchen string.
  3. Pat the fillet dry and sprinkle all over with the Umami Steak Powder, rubbing it into the fillet.
  4. Set the roasting pan over 2 stove-top burner. Add a third of the olive oil and heat over medium-high heat until shimmering. Brown the fillet on all sides, about 10 minutes. Remove and stand, while lightly frying half the button mushrooms and half the porcini mushrooms in the same pan. Add the bread crumbs and mix well. Remove from the stove.
  5. Sprinkle the porcini powder evenly on top of tenderloin and then pack the breadcrumb/mushroom mixture around the fillet.
  6. Roast in oven until thermometer inserted diagonally 6cm into center of the thickest part of meat registers 48°C (about 30 minutes).
  7. Toward end of roasting tenderloin, stir together half of the porcini butter and all of the flour. Heat remaining tablespoon olive oil in a heavy skillet over medium-high heat until shimmering, and sauté the other half of the button and porcini mushrooms with 1/4 teaspoon of salt and pepper, until all the liquid released by the mushrooms evaporates and the mushrooms are tender and golden (10 minutes).
  8. Add 2 cups of the beef stock to the skillet and simmer, stirring up the brown bits for about a minute. Remove skillet from heat while you transfer the fillet to a cutting board to let it stand for 15 minutes (internal temperature will rise a bit to medium-rare stage).
  9. Meanwhile, bring the mushroom mixture back to a boil and whisk in the balance of the porcini butter. Reduce the heat and simmer, whisking occasionally until thickened, about 2 minutes. Stir in the spring onions and season with salt and pepper to taste.
  10. Cut the fillet into 2cm thick slices, discarding the string as you go. Serve with the sauce.

Cooks' Notes:

  • Whole fillets can come in various stages of trimming, particularly those from large retailers. Some still have the chain attached, which is a long, thin, loose muscle hanging onto one side of the tenderloin. This you'll want to remove and save for something like kebabs. Whether the fillet comes trimmed or not, make sure there is no fat or silverskin left on the outside. If there is, remove it yourself with a sharp knife.
  • The Great Cape’s Pure Porcini Mushroom Powder should be stored in the fridge or freezer for longevity and to keep the strong flavour intact. Heat causes it to release its Umami wonderfulness, so save that for the pan!
  • You can make the Porcini butter a day ahead of time by melting 250g of good quality salted butter (do not let it sizzle) and stirring in a teaspoon of Pure Porcini Mushroom Powder, and then setting in the fridge.