Wash the romaine and baby greens thoroughly and cut them into bite-sized pieces.
Slice cherry tomatoes, cucumber, and red onion thinly.
Crumble the feta cheese into small pieces.
Slice the black olives.
Put all the vegetables and ingredients into a bowl and mix well.
Add olive oil, lemon juice, and wasabi as dressing, then toss to coat evenly.
Adjust the taste with salt and black pepper.
Serve on a plate.