Make the Tofu Feta: In a jar, mix lemon juice, vinegar, olive oil, oregano, salt, garlic powder, and black pepper.
Add tofu cubes, seal the jar, and shake well. Let it marinate for at least 1 hour (overnight for best flavor).
Assemble the Salad: In a large bowl, combine mixed greens, tomatoes, cucumber, onion, and olives.
Prepare the Dressing: Whisk together olive oil, lemon juice, mustard, maple syrup, salt, and pepper in a small bowl.
Toss & Serve: Add marinated tofu to the salad, drizzle with dressing, and toss lightly. Enjoy!