Cut the tofu into bite-sized pieces.
Heat oil in a pan and grill the tofu until golden brown on both sides.
Make the sauce by mixing soy sauce, water, minced garlic, red pepper powder, green onion, sesame oil, and sugar.
Pour the sauce over the grilled tofu and simmer over medium-low heat.
When the sauce is reduced, sprinkle green onion and sesame seeds to finish.