Remove excess water from the tofu and cut it into bite-sized pieces.
Drain the oil from the canned tuna using a strainer.
Finely chop the onion and green onion.
Heat cooking oil in a pan and sauté the onion and green onion.
Add the tofu and tuna and stir-fry over medium heat.
Season with soy sauce and pepper.
Once the ingredients are evenly mixed and cooked through, it's ready to serve.