Katsuo Tempura is a crispy and flavorful dish that features battered and deep-fried bonito fish. To make Katsuo Tempura, you will need bonito fillets, tempura batter mix, ice-cold water, vegetable oil for frying, and tempura dipping sauce. Start by preparing the tempura batter according to the package instructions. Dip the bonito fillets into the batter, making sure they are evenly coated. Heat vegetable oil in a deep fryer or a large pot to about 350°F (175°C). Carefully place the battered bonito fillets into the hot oil and fry until they turn golden brown and crispy. Remove the fried fish from the oil and let them drain on a paper towel. Serve the Katsuo Tempura with tempura dipping sauce on the side. The crispy and delicate bonito fish, paired with the light and airy tempura batter, creates a delightful contrast of textures in this dish.