Press the tofu between paper towels for 15 minutes to remove excess moisture, then cut into 1-inch cubes.
Place tofu cubes in a bowl and toss gently with cornstarch until evenly coated.
Heat the sesame oil in a large non-stick skillet or wok over medium-high heat.
Add the tofu to the pan in a single layer and sear until golden and crispy on all sides, then remove and set aside.
In the same skillet, add the broccoli, bell pepper, and edamame with a tablespoon of water; cover and steam for 2 minutes.
While the vegetables cook, whisk together the tamari, rice vinegar, grated ginger, and minced garlic in a small bowl.
Uncover the skillet, return the tofu to the pan, and pour the sauce over the mixture.
Toss everything together for 1-2 minutes until the sauce thickens and coats the ingredients.
Serve immediately garnished with red pepper flakes and sesame seeds.