Start by pressing the tofu between paper towels and a heavy object for about 15 minutes to remove excess moisture. Once pressed, cut the tofu into 1-inch cubes.
In a bowl, toss the tofu cubes with cornstarch until they are evenly coated. This will give the tofu a crispy texture when cooked.
Heat 1 tablespoon of vegetable oil in a large pan or wok over medium-high heat. Once hot, add the tofu cubes. Cook until golden brown and crispy on all sides, about 8-10 minutes. Remove the tofu from the pan and set aside.
In the same pan, add the remaining tablespoon of oil. Toss in the broccoli, bell pepper, carrot, and snap peas. Stir-fry the vegetables for about 5-7 minutes, or until they are tender yet crisp.
Add the minced garlic and ginger to the pan, sautéing for an additional minute until fragrant.
While the veggies are cooking, in a small bowl, mix together the soy sauce, maple syrup, rice vinegar, and sesame oil.
Return the tofu to the pan, and pour the teriyaki sauce over the stir-fried veggies and tofu. Toss everything together to coat well, allowing the sauce to heat through for about 2-3 minutes.
Remove from heat and garnish with sesame seeds and sliced green onions before serving.