Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Press the extra-firm tofu for 15 minutes to remove excess moisture, then cut into 1/2-inch uniform cubes.
In a large mixing bowl, combine the cauliflower florets and tofu cubes.
Drizzle with olive oil and sprinkle with sea salt, black pepper, garlic powder, and smoked paprika, tossing until every piece is evenly coated.
Spread the mixture in a single layer on the prepared baking sheet, ensuring they are not overcrowded to allow for proper browning.
Roast for 25 to 30 minutes, flipping halfway through, until the cauliflower is tender and the tofu cubes are golden and crispy.
While the vegetables roast, whisk together the Greek yogurt, tahini, lemon juice, and water in a small bowl until the sauce is smooth and pourable.
Plate the roasted cauliflower and tofu, drizzle the tahini sauce over the top, and garnish with freshly chopped parsley.