Cut cauliflower into small chunks and put it in a large mixing bowl.
Pour a few TB of olive oil over the cauliflower.
Season generously with salt, pepper and toss gently until evenly coated.
Put cauliflower on a baking sheet and bake for 25-30 minutes.
Check the cauliflower half way through to see that it's cooking evenly.
When done roasting, set cauliflower aside to cool in a large bowl.
Combine all remaining ingredients in a bowl and gently fold it together.
Now add in the roasted cauliflower.
Sprinkle roasted walnuts on top.
Enjoy your big, beautiful bowl of colors and nutrients!
I doubt there will be any but you can store leftovers in the fridge.
Notes
Anything can be substituted with these ingredients; beans, nuts, herbs, oils and even the veggies. Use what you have on hand and make your own veggie tabbouleh!