Cut the bell peppers in half, remove seeds and stems, and slice into bite-sized pieces. Cut the fried tofu into halves and then into 2cm-wide slices.

Pat the yellowtail fillets dry with paper towels, cut into quarters, sprinkle with salt, and coat both sides with cornstarch.

Heat salad oil in a frying pan over medium heat. Add the yellowtail and tofu, cook for 2–3 minutes until browned. Flip, cover, and cook on low heat for 3–4 minutes until the yellowtail is cooked through. Add bell peppers and stir-fry briefly.

Add sake, BBQ sauce, and gochujang to the pan. Simmer on low heat until the sauce thickens and coats the ingredients.