Press the tofu for at least 20 minutes to remove excess moisture, then cut it into bite-sized cubes.
Toss the tofu cubes with 2 tablespoons of cornstarch until evenly coated.
Whisk together the soy sauce, hoisin sauce, maple syrup, sesame oil, 1 tablespoon cornstarch, and vegetable broth in a small bowl.
Heat 1 tablespoon of vegetable oil in a large skillet or wok over medium-high heat.
Cook the tofu for 8 to 10 minutes, turning occasionally, until golden and crispy. Transfer to a plate.
Add the remaining tablespoon of oil to the skillet.
Stir-fry the broccoli, carrots, bell pepper, mushrooms, and snap peas for about 5 to 6 minutes until crisp-tender.
Add the garlic and ginger and cook for 30 seconds until fragrant.
Return the crispy tofu to the skillet.
Pour in the prepared sauce and stir until everything is evenly coated and the sauce thickens.
Garnish with green onions and sesame seeds before serving.