For The Short Rib:

1. Set a large pot of water or sous vide bath fitted with a sous vide machine to 69℉ / 20℃.
2. Pat dry the ribs with a paper towel. Season generously with salt and pepper and vacuum-seal.
3. Submerge the short rib, using a weight if necessary, and sous vide for 48 hours.
4. Remove the vacuum bags from the water, keeping the meat sealed, and place on a sheet pan. Place another sheet pan on top, weigh it down with about 15-20 lbs of pressure, and refrigerate overnight.
5. Remove the ribs from the vacuum bag, and split them in half between the bones.
6. Next, remove the ribs from the bone, cutting as close as possible to the bone. Then cut those pieces into 2 1/2-inch wide by 5-6-inch long logs.
7. Optionally, sear these pieces, on all sides, in a large sauté pan over medium-high heat until caramelized all over.
8. Brush the ribs on all sides with a light coating of mustard and season to taste with salt. Let rest while making the duxelle.

‍For The Miso Port Duxelles:

1. Place the button and shiitake mushrooms in a food processor and pulse until finely chopped but not a paste.
2. In a medium saucepan over medium heat add the butter and melt. Once the butter is hot, add in the shallot and cook for about 3 minutes, or until softened. Mix in the mushrooms, season with salt and add in the rosemary. Cook for 5-6 minutes, or until the mushrooms cook down and any liquid released is evaporated.
3. Deglaze the pan with sherry wine and cook until all the liquid is gone, stirring occasionally.
4. Remove the pan from heat and discard the rosemary sprigs. Stir in the miso paste, truffle and garlic until combined and set aside to cool slightly.

‍For The Crepes:

1. In a medium mixing bowl, whisk together the eggs, melted butter, milk, and salt until homogenous. Whisk in the flour until a smooth batter forms.
2. Heat a 12-inch nonstick skillet over medium heat and spray with cooking spray.
3. Once hot, add about  ⅓ cup of batter, swirling the batter around the pan to evenly coat the bottom in an even layer. Cook for 30 - 45 seconds, or until lightly browned and cooked through. Flip and cook for another 25 - 30 seconds or until beginning to brown on the second side. Remove to a plate and repeat until you use all the batter or have at least 5 crepes. Set aside to cool slightly.

‍To Assemble:

1. Preheat oven to 475℉ / 246℃.
2. Place 2 sheets of plastic wrap on a work surface, slightly overlapping each other.
3. Place 1 crepe on top of the plastic wrap and top with 3-5 slices of shingled prosciutto. Add a quarter of the duxelle mixture to the top of the prosciutto and spread, from edge to edge, in one even layer.
4. Place a short rib at the bottom of the crepe, tightly roll the crepe around the meat, using the plastic wrap to help guide the rolling. Tuck in the sides of the crepe and tightly seal it together with the plastic wrap. Wrap tightly and refrigerate while you assemble the remaining crepes.
5. In a small bowl whisk together the egg yolks and water until homogenous. Set egg wash aside.
6. Lightly dust a clean work surface with bench flour. Roll one sheet of puff pastry into a rectangle, about 10 x 14-inches and ¼-inch thick.
7. Remove the plastic wrap from one of the short ribs wrapped in crepe and place it at the bottom of the puff pastry. Trim the dough into a rectangle so that when you roll the puff pastry the two end edges will just meet to cover the short rib log. Set aside excess pastry dough.
8. Brush the edge of the puff pastry with egg wash and roll it up to completely cover the log. Trim the sides of the dough so there is just about 1-inch of excess dough on either side, and pinch it together to seal tight. Wrap in plastic to close the edges completely and place in the fridge for at least 20 minutes. Repeat with the rest of the ribs and puff pastry dough.
9. Remove the plastic wrap from each wellington and place on a parchment lined sheet pan. Brush each with egg wash all over. If you have any excess dough you can use that to add a decorative finish to the wellingtons or alternatively use a sharp knife to create a pattern on top of the puff pastry or just leave them as is.
10. Sprinkle flakey sea salt over the tops of each and bake for 20-25 minutes or until the pastry is golden brown and cooked through.
11.  Remove from the oven and let it rest for 5 minutes before slicing and serving.