Begin by pressing the tofu for at least 15 minutes to remove excess water, then cut it into evenly sized cubes.
Heat a heavy-bottomed skillet over medium-high heat and add a splash of sesame oil.
Add the tofu cubes to the hot pan in a single layer, pressing down gently. Let them cook undisturbed for about 3-4 minutes until edges turn golden brown.
Carefully flip the tofu cubes using a spatula or tongs, then cook for another 3-4 minutes until all sides are crispy and evenly browned.
While the tofu cooks, whisk together soy sauce, mirin, brown sugar, minced garlic, and minced ginger in a small bowl to make the glaze.
Once the tofu is crispy, pour the prepared sauce over the pan. Carefully stir to coat all the tofu pieces evenly.
Allow the sauce to bubble and thicken for about 2-3 minutes, turning the tofu to ensure each piece is coated in a shiny, sticky glaze.
Remove the skillet from heat once the sauce is thick and glossy, and the tofu is caramelized around the edges.
Transfer the sticky tofu to a serving dish or plate, and sprinkle with toasted sesame seeds if desired.
Serve immediately while the glaze is shiny and the tofu is crisp on the outside, tender inside, ready to be enjoyed.
