If you don't have pre-cooked brisket: braise 600 g beef brisket in stock with aromatics until fork-tender (about 2–3 hours). Cool and finely mince or pulse in a food processor to a coarse paste. Use 400 g of the minced brisket for the filling, reserving any extra for another use.

Finely dice the Fungi Jon (or rehydrated/dried shiitake) mushrooms and the yellow onion. If using dried mushrooms, rehydrate in warm water 20–30 minutes, squeeze out excess water and finely chop.

In a medium bowl combine minced brisket, mushrooms, diced onion, grated ginger, minced garlic, and sliced green onions. Mix gently to combine.

Add 2 tbs light soy sauce, 1 tsp sesame oil, 1 tsp rice vinegar, 1 tsp salt and 1 tsp ground black pepper. Stir until the mixture is cohesive. Taste and adjust seasoning — the filling should be slightly seasoned because wrappers dilute flavor when cooked. If filling seems very wet, chill 10–15 minutes to firm up for easier wrapping.

Dough & assembly

Lightly dust a work surface with cornstarch to prevent sticking. Keep gyoza wrappers covered under a damp towel to prevent drying.

Place one wrapper in your palm or on the work surface. Spoon about 1 heaping teaspoon (approximately 12 g) of filling into the center of the wrapper. Do not overfill — leave a clean rim around the edge for sealing.

Dip a finger into cold water and run it around half the wrapper edge. Fold the wrapper in half over the filling to form a semicircle. Starting from one end, make 2–3 small pleats along the edge, pressing each pleat to seal firmly; you should create a pleated crescent-shaped gyoza. Repeat with remaining wrappers and filling. Place finished gyoza on a tray lined with parchment, not touching each other.

Pan-fry & steaming

Heat a large nonstick skillet or cast-iron pan over medium-high heat. Add 2 tbs neutral oil and swirl to coat.

Add gyoza to the pan in a single layer, flat side down, working in batches if necessary. Fry undisturbed for 2–3 minutes until the bottoms are golden brown.

Carefully pour 120 ml water into the pan (it will steam and sputter). Immediately cover with a tight-fitting lid and reduce heat to medium-low. Steam for 4–5 minutes until the wrappers become translucent and filling is heated through.

Remove lid and increase heat to medium-high to evaporate remaining water, about 1 minute. Let the bottoms crisp again for 30–60 seconds.

Use a spatula to transfer gyoza to a platter. Repeat with remaining gyoza, adding a little more oil if pan gets dry.

Black vinegar dipping sauce

In a small bowl combine 3 tbs Chinkiang black vinegar and 1 tbs light soy sauce. Stir in 1 tsp sesame oil and, if desired, 1 tsp chili oil for heat.

Garnish the sauce with 1 tbs thinly sliced green onion. Taste and adjust — add a few drops of water if the vinegar is too strong, or a pinch of sugar to balance acidity.

Serve the gyoza hot with the black vinegar dipping sauce alongside.