Press the tofu thoroughly to remove excess moisture. Place the tofu block between paper towels, set a heavy plate on top, and let sit for at least 30 minutes. For best results, press for up to 2 hours, changing the paper towels halfway through.
Cut the pressed tofu into 1-inch cubes or triangles of even size to ensure uniform cooking.
Prepare the cornstarch coating by placing cornstarch in a shallow bowl. Toss tofu pieces gently until all sides are lightly dusted, shaking off any excess.
Heat oil in a large non-stick skillet over medium-high heat until shimmering but not smoking. The right temperature is crucial for developing crispiness without burning.
Add the coated tofu to the hot pan in a single layer, ensuring pieces don’t touch. Work in batches if necessary – overcrowding will steam rather than crisp the tofu.
Pan-fry for 3-4 minutes per side without disturbing, until all sides develop a golden-brown crust. Patience is key here for achieving maximum crispiness.
While tofu cooks, whisk together the miso paste, mirin, rice vinegar, maple syrup, soy sauce, ginger, and garlic in a small bowl until smooth.
Reduce heat to medium-low once tofu is crispy on all sides, then pour the miso mixture over the tofu.
Gently toss the tofu pieces to coat evenly with the glaze, cooking for another 2-3 minutes until the sauce thickens and caramelizes, creating a glossy coating.
Transfer to a serving plate immediately and garnish with sliced green onions and toasted sesame seeds.