Preheat your oven to 400°F and line a small baking sheet with parchment paper.
Drain the tofu and press it firmly between paper towels to remove as much moisture as possible, then cut into 1-inch cubes.
In a small bowl, whisk together the olive oil, dried oregano, garlic powder, sea salt, and black pepper.
Toss the tofu cubes in the oil mixture until evenly coated, then spread them in a single layer on the prepared baking sheet.
Bake for 20-25 minutes, flipping halfway through, until the tofu is golden brown and firm to the touch.
While the tofu bakes, halve the cherry tomatoes and dice the cucumber.
Assemble the bowl by placing the baby spinach at the base, followed by the cooked quinoa, tomatoes, and cucumber.
Top the bowl with the warm baked tofu and drizzle the fresh lemon juice over the entire dish before serving.