Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Press the extra firm tofu with a clean kitchen towel to remove excess moisture, then cut it into 1/2-inch cubes.
Rinse and drain the canned chickpeas, then pat them dry with a paper towel to ensure they become crispy during roasting.
In a large mixing bowl, toss the tofu cubes, chickpeas, broccoli florets, and sliced bell pepper with the olive oil, garlic powder, onion powder, sea salt, and black pepper.
Spread the mixture in a single, even layer on the prepared baking sheet to allow for proper browning.
Roast for 25-30 minutes, tossing the ingredients halfway through, until the vegetables are tender and the tofu is golden and firm.
Remove the sheet pan from the oven and immediately sprinkle the nutritional yeast and hemp hearts over the hot ingredients.
Whisk together the lemon juice and tahini in a small bowl until smooth, adding a teaspoon of water if needed to reach a pourable consistency.
Transfer the roasted mixture to a bowl and finish by drizzling the tahini dressing over the top.