Trim king oyster mushrooms: remove tough bottoms and slice each mushroom lengthwise into 2 or 3 thick slabs (about 1/2–3/4-inch thick) so they resemble fillets. If using whole mushrooms for a rounded 'fish' shape, keep stems intact and make a few shallow crosswise slashes to help absorb marinade.

Press and shape tofu (optional)

If using tofu for added density, press for 20–30 minutes to remove excess water, then slice into slabs roughly the same size as the mushroom pieces. Pat dry.

Lay a nori sheet flat and place a mushroom or tofu slab in the center; brush a light layer of marinade (see next section) on the exposed surfaces, then wrap the nori around the piece. The nori adds 'sea' flavor and a charred, savory crust reminiscent of fish skin. Repeat for all pieces.

Marinade / glaze (umi-forward smoky-sweet)

Make the marinade

In a bowl, whisk together light soy sauce, mirin, rice vinegar, maple syrup, sesame oil, grated ginger, minced garlic, and vegan dashi or kombu-shiitake infusion. Stir in smoked salt and lemon juice. Taste and adjust: it should be balanced sweet-salty-acid with a hint of smoke.

Marinate

Reserve 2 tablespoons (approx. 30 ml) of the marinade for brushing during and after grilling. Place the wrapped mushroom/tofu pieces in a shallow dish or resealable bag and pour the remaining marinade over them. Marinate at room temperature for 20–30 minutes or up to 1 hour in the fridge for deeper flavor. Turn once halfway through so both sides absorb flavors.

Charcoal grilling

Prepare the grill

Light the charcoal and wait until it reaches medium-hot (charcoal glowing with a thin white ash coating). Set up for two-zone cooking if possible: coals concentrated to one side for direct heat and a cooler side for finishing. Oil the grate just before cooking: dip a wad of paper towel in neutral oil and, using tongs, oil the hot grate to prevent sticking.

Initial sear

Place the marinated nori-wrapped mushroom/tofu pieces over direct medium heat. Sear 2–3 minutes per side, without moving, until you get good char marks and the nori crisps. Use tongs or a fish spatula to flip carefully to avoid tearing the nori.

Cook through and glaze

After searing, move pieces to the cooler side of the grill (indirect heat) to finish cooking gently for another 3–5 minutes per side depending on thickness. Brush with reserved marinade once halfway through and again in the last minute. Watch closely to avoid burning the sugars in the glaze; reduce direct heat or move farther from coals if flare-ups occur.

Check for doneness: mushrooms should be tender and slightly springy, tofu warmed through with browned edges. The nori should be crisp and deeply flavored.

Finishing & garnish

Rest

Transfer grilled pieces to a platter and let rest 2 minutes to allow juices and glaze to settle.

Garnish and serve

Sprinkle sliced scallions and toasted sesame seeds over the pieces, add microgreens or cilantro if using, and serve with lemon wedges. Offer extra reserved marinade warmed briefly (do not use marinade that contacted raw tofu/mushroom unless boiled) or a small bowl of warmed marinade reduced for dipping.

Serve immediately while hot. Recommend serving with steamed rice, pickled vegetables, or a crisp salad to complement the smoky, umami flavors.