Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Press the firm tofu between paper towels to remove excess moisture, then cut into 1-inch cubes.
In a large bowl, combine the tofu cubes, broccoli florets, and bell pepper strips.
Drizzle with olive oil and sprinkle with sea salt, black pepper, and dried oregano, tossing well to coat everything evenly.
Spread the mixture in a single layer on the prepared baking sheet and roast for 25 minutes, flipping halfway through, until the tofu is crispy and the vegetables are tender.
While the vegetables roast, whisk together the Greek yogurt and lemon juice in a small bowl until smooth.
Transfer the roasted tofu and vegetables to a serving bowl, then top with crumbled feta cheese and hemp hearts.
Finish by drizzling the lemon-yogurt sauce over the top and serve immediately.