Cut the tofu into 1cm thick slices.
Lightly sprinkle salt on the tofu to season it.
Heat cooking oil in a pan and grill the tofu until golden brown.
Mix soy sauce, water, red pepper flakes, minced garlic, sugar, and sesame oil to make the sauce.
Pour the sauce over the grilled tofu and simmer on medium-low heat.
When the sauce has thickened, garnish with chopped green onion and sesame seeds.