Preheat oven to 300F
In a frying pan on medium heat, drizzle vegetable oil.
Add onion to the pan and cook for 1 minute or until onions start to sweat.
Add garlic, carrot, celery, mushrooms and cook for 10 minutes until vegetables soften.
Add kale to pan and cook for 1-2 minutes until kale is a vibrant green and vegetables have softened. Turn off the heat to the stove. To the warm vegetables, add dried oregano, dried thyme, dried parsley and cayenne pepper.
In a large mixing bowl, transfer vegetable herb mixture to cool.
Across the top of the vegetable herb mixture, sprinkle dried breadcrumbs, table salt, black pepper and gelatin. Add Dijon mustard to the mixture.
Add ground/ mince meat to the large bowl.
Add 2 eggs to the large bowl.
Use your hands or a rubber spatula to mix the ground/ mince meat with vegetables and eggs into a cohesive mixture.
In a small bowl, crack an egg open and leave egg as is in the bowl.
On a lightly floured surface, attach two pieces of puff pastry together by brushing egg white onto a 1” strip of one edge and overlapping the second piece of puff pastry by 1 inch. Roll the puff pastry into a 10 x 14” rectangle.
Brush egg white across the surface of the puff pastry. This will be a glue and prevent the bottom of the puff pastry from getting soggy.
Transfer the contents of the meat vegetable mixture onto the puff pastry in a log shape, leaving 1 1/2” from both ends of the length of the mince/ground meat log.
Seal the meat log lengthwise by bringing the edges of the puff pastry on the shorter width to wrap and tightly overlap and seal across the length of the mince/ground meat log.
Seal the ends of the meat log by pushing the overlapped seam down on the ends of the log and pull up the bottom layer of the puff pastry to seal the ends of the log. Pinch and seal any openings in the puff pastry.
Lay a piece of parchment onto a baking sheet.
Quickly flip and transfer the puff pastry meat log onto the parchment laid baking sheet.
In the small bowl with the egg, quickly scramble the egg. Brush the egg mixture across the top and sides of the puff pastry meat log.
Use a sharp knife to slice parallel slice marks into the top of the puff pastry.
Sprinkle kosher salt on top of the puff pastry.
Place the puff pastry meat log on the pan into the oven. Allow to cook for 50 minutes until the internal temperature is 140F. Puff pastry will be lightly brown.
Increase the oven temperature to 400F to broil and keenly watch the puff pastry turn a golden brown. It can be very quick, within 3 minutes! Remove from oven when the color of puff pastry is as desired.
Allow the Mince/ Ground Meat Wellington to rest on the parchment baking sheet for at least 20 minutes at room temperature undisturbed.
Using a sharp knife to slice into 1 ½ inch slice from the end for the first cut (this has the extra puff pastry on the end) and slice into ¾ to 1 inch widths for further slices.