Katsuobushi-style preservation can be adapted to many raw materials—as Noma Kyoto has shown with “pumpkin-bushi” and “corn-bushi”—but every stage needs ingredient-specific tuning. First, steam the prepared pieces at 90-100 °C until their core stays above 90 °C for 20–30 min; this gelatinises starches, sets proteins, and drives off surface moisture without letting soft vegetables collapse. Next, dry and smoke in repeated hot-smoke cycles: hold the blocks at 60-75 °C for 6–8 h per session using a mild hardwood (e.g., cherry or oak), with overnight rest periods so internal moisture can migrate outward; total smoke time may be 24 h for delicate produce or up to 100 h for fish, and humidity must be kept below ~60 %—move racks to a dehydrator or ventilated room if rain or damp weather stalls drying. When the moisture content falls below ~25 %, inoculate the surface with a light mist of kōji mold (traditionally Aspergillus glaucus for fish, but A. oryzae performs reliably on vegetables). Age the blocks at 15–20 °C and ~65 % RH for one to three months, brushing off the mold bloom, re-smoking briefly, and re-inoculating between cycles; three to four such rounds leave the product rock-hard, shelf-stable (water activity < 0.75), and intensely savory.