Golden Hamburg Steak: A Full Copycat Recipe (Test Batch Edition)

Cut the onion into roughly 7-8mm pieces. Cut them slightly large to account for shrinkage after cooking.

Sauté the onion. Don't take it all the way to golden brown; stop just short of caramelized, before it goes limp.

Clean the dirt off the mushroom stem ends, grind the mushrooms in a food processor, and sauté them in vegetable oil.

Knead the ground meat blend thoroughly until sticky. Add the roughly chopped coarse-ground meat (25% of the total meat) and the beef tallow. If the coarse grind is too coarse, grind it finer in a food processor before adding.

Add the sautéed onion and mushrooms, egg white (dried egg white), gelatin, wheat flour, wheat dietary fiber, rice flour, concentrated beef bouillon powder, sugar, salt, and pepper, and mix together.

Shape the mixture, tap it lightly to release air pockets, then chill it in the refrigerator until cooking. Don't flatten it too much or it will shrink; watch the thickness.

For the sauce, press the sautéed onion and mushrooms through a sieve. The original sauce has almost no graininess, so remove as much vegetable body as possible.

Sauté the sieved vegetables in butter, then add the red wine, tomato paste, bouillon, fond de veau, natural cheese, and canned demi-glace sauce.

Reduce the sauce and finish it with caramel coloring for color. Be careful not to reduce it too far and drive off too much liquid.

Grill over direct high heat for 3 minutes, until the surface is crisp and browned. Line the tray with parchment paper.

Place the grilled patty and the sauce in a heatproof bag, press out the air, and seal it.

Cook through in a water bath at low temperature.