Charred Bavette Onions

Ingredients

• 510 grams | 18 ounces bavette (skirt steak)
• 3 grams | 1 ½ teaspoons transglutaminase
• 40 grams | 1.5 ounces Périgord truffles
• kosher salt
• 100 grams | ½ cup rendered beef fat, plus more for finishing
• 300 grams | 1 ¼ cups veal jus, warmed
• charred onion crust
• 24 grams | 2 tablespoons Twin Sisters olive oil
• Maldon sea salt

• 400 grams | 2 ⅔ cups sliced yellow onions
• 200 grams | ¾ cup heavy cream
• 800 grams | 3 ¼ cups whole milk
• 44 grams | ⅓ cup kuzu root starch
• kosher salt

• 100 grams | ½ cup rendered beef fat
• 100 grams | ½ cup unsalted butter
• 4 | pearl onions
• kosher salt
• 4 | spring onions, white part only (2 inches/5 centimeters long, from root end)
• 4 | tiny ramps with roots intact

1. Périgord truffles, sliced wild watercress
FOR THE BAVETTE:
2. Trim the bavette of any fat and sinew and place between 2 sheets of plastic wrap. Using a butchery mallet, flatten the bavette to a uniform ½ inch (12millimeters) thick. Fill a small strainer with half of the transglutaminese. Tap the side of the strainer with a spoon to dust the transglutaminese thinly and evenly over the bavette. Using a fine-tooth grater, grate the truffles evenly over the bavette. Then dust the bavette with the remaining transglutaminese. Cut the bavette in half with the grain. Lay one half of the bavette, prepared side down, on top of its corresponding half so they match up perfectly. Wrap the stacked halves tightly in plastic wrap, place in a shallow dish, and top with a 4.5-kilogram (10-pound) weight. Refrigerate for 6 hours.
FOR THE ONION JAM:
3. Combine the onions, cream, and 300 grams (1 ¼ cups) of the milk in a rondeau. Cover the surface with a piece of parchment paper and heat slowly to a low simmer. Cook for 35 minutes, until the liquid has reduced by half. Transfer the contents of the pan to a blender and mix on high speed for 4 minutes, until a smooth puree (soubise) forms. Strain the puree through a chinois into a heatproof bowl. Have ready an ice bath. Combine the remaining 500 grams (2 cups) of milk and the kuzu root starch in a saucepan and bring to a boil over high heat while whisking continuously. When the milk has thickened, cook for an additional 30 seconds, then strain through the chinois into the bowl holding the onion puree. Fold the two mixtures together and season with kosher salt. Nest the bowl in the ice bath and let the jam cool completely. Transfer the jam to an airtight container and refrigerate until serving.
FOR THE ONION CONFIT:
4. Combine the beef fat and butter in a small saucepan and melt over low heat to combine. Lightly coat the pearl onions with the melted fat and season with kosher salt. Transfer the pearl onions to a vacuum bag and seal on high. Repeat with the spring onions, then reserve any remaining fat for serving. Cook the pearl and spring onions in a steam oven set at 200°F (95°C); the spring onions are ready in 15 minutes and the pearl onions are ready in 20 minutes. Remove from the oven and let cool to room temperature, then remove from the bags and pat dry with paper towels. Store the onions in an airtight container in the refrigerator until serving.
FOR THE CHARRED ONION CRUST:
5. Put the dried onions and morels in a blender and mix on high speed for 2 minutes, until a fine powder forms. Add the panko, sugar, and Maldon salt and mix on high speed for 2 minutes longer. Transfer the powder to a bowl, add the flour and vegetable ash, and stir to mix. Reserve in a cool, dry area.
FOR THE GLAZED SALSIFY:
6. In a large bowl or other container, dissolve the ascorbic acid in the water. Peel each salsify evenly on all sides to create a perfect cylinder, then immerse in the acidulated water to prevent oxidation. When all of the salsifies are peeled, drain, pat dry on paper towels, and season lightly with oil and kosher salt. Arrange the salsify cylinders neatly in a vacuum bag and seal on high. Cook in a steam oven set at 200°F (95°C) for 20 minutes. Remove the bag from the oven and cool in an ice bath for 5 minutes. Remove the cylinders from the bag and cut crosswise into pieces 1 inch (2.5 centimeters) long. Put a little water (about 30 grams/2 tablespoons) in a small sauté pan over medium heat. When the water begins to boil, whisk in a little of the butter alternately with a little of the beef fat until all of the butter and beef fat are in the pan. As soon as the mixture begins to emulsify, turn down the heat and continue to whisk until emulsified. Add the salsify pieces and heat slowly. When the salsify is well coated with the fat, season with kosher salt. Remove from the pan and keep warm until needed.
FOR THE BEEF JUS:
7. Place a sauté pan over low heat. Add the extra virgin olive oil and then the shallots and stir continuously so the shallots do not caramelize. When the shallots are translucent, add the Madeira and reduce until the pan is dry. Meanwhile, heat the beef jus in a small saucepan over low heat. When the shallots are ready, add them to the jus along with the truffles, Twin Sisters oil, and vinegar. Taste and season with Maldon salt, if needed; keep warm until ready to serve.
TO SERVE:
8. To finish the bavette preparation, reheat the bags holding the bavette portions in a hot-water bath set at 138°F (59°C) for 15 minutes. Remove from the bags and pat dry on paper towels. Season each portion lightly on all sides with kosher salt one more time. Using a pastry brush, lightly coat each portion on all sides with the veal jus, then dredge in the charred onion crust and tap off any excess.
9. Spray a sheet of parchment paper with nonstick cooking spray and place near the stove top. Heat a cast-iron skillet over high heat and add 20 grams (1 ½ tablespoons) of beef fat. When the fat is hot, add the bavette portions and lightly crisp on all sides (about 15 seconds per side). Use a slotted flat spatula to turn the bavette portions, being careful to maintain an even layer of crust. When the bavette portions are ready, transfer them to the prepared parchment to rest in a warm place for at least 4 minutes and no more than 8 minutes.
10. To reheat the onions, place the reserved beef fat in a sauté pan and melt over medium heat. Add the pearl and spring onions and warm through, being careful to not caramelize the onions. Add the ramps during the last second or two just to wilt slightly. Season with kosher salt. After resting, cut a very thin slice against the grain off of one side of each meat portion to show the interior. Brush the cut side of each meat portion with olive oil and season with Maldon salt. Place the beef in the center of a plate and garnish with the onion jam; the confit of spring onions, pearl onions, and ramps; and the salsify. Finish the plate with the beef jus, truffle slices, and watercress.