Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper.
Drain the tofu and press it for at least 15 minutes to remove excess moisture. Then, cut the tofu into 1-inch cubes.
In a medium bowl, combine the tofu cubes with coconut aminos, garlic powder, and smoked paprika. Toss gently to evenly coat.
Sprinkle the cornstarch over the tofu and toss again until each cube is lightly coated. This will help achieve a crispy texture when baked.
Cut the broccoli into florets, slice the red bell pepper into strips, and cut the red onion into wedges. Place the vegetables in a separate bowl.
Drizzle the vegetables with olive oil and season with a pinch of salt and pepper if desired. Toss to ensure even coating.
Arrange the tofu cubes on the prepared baking sheet in a single layer. Place the baking sheet with tofu in the preheated oven and bake for 25 minutes, flipping halfway through, until the tofu turns golden and crispy.
Halfway through the tofu baking time, spread the vegetables on another baking sheet and roast in the oven for about 20 minutes until tender and slightly caramelized.
Once both the tofu and vegetables are cooked, plate them together and serve warm.